I am trying to create an Array which would let the user input up to 80 characters and then when the program halts, for the program to return the amount of times each vowel shows up in the Array. I successfully got it to work last week, but the coding got lost and I had to do it from scratch.
Edit: The problem I am having is that based on the current structure, all the counters still return 0 at the end.
I remember that I used the following coding, but I am having issues with the counters actually working. I think I had the segment for the counters in a loop of its own, but I can't remember it.
I also want the program to halt if the user presses ENTER, but I have no idea how that works.
Any help would be appreciated.
#include <iostream>
#include <iostream>
using namespace std;
int main()
{
int x = 0;
char thisArray[80];
int aCounter = 0, eCounter = 0, iCounter = 0, oCounter = 0, uCounter = 0;
cout << "Please enter up to 80 characters and you will be told" << endl;
cout << "how many times each vowel is in the array." << endl;
do{
cout << "Please enter a character" << endl;
cin >> thisArray;
x++;
} while (x < 80);
for (x = 0; x <= thisArray[x]; x++) {
if (thisArray[x] == 'a')
aCounter = aCounter + 1;
else if (thisArray[x] == 'e')
eCounter = eCounter + 1;
else if (thisArray[x] == 'i')
iCounter = iCounter + 1;
else if (thisArray[x] == 'o')
oCounter = oCounter + 1;
else if (thisArray[x] == 'u')
uCounter = uCounter + 1;
}
cout << "Vowel count:" << endl;
cout << "Total number of A's." << aCounter << endl;
cout << "Total number of E's." << eCounter << endl;
cout << "Total number of I's." << iCounter << endl;
cout << "Total number of O's." << oCounter << endl;
cout << "Total number of U's." << uCounter << endl;
system("pause");
}
The do loop you are using is not correct. It will try to read a string 80 times, and will store only the last string. Each of those strings will contain only non-whitespace characters.
Change the do loop so that you read one character at a time, using unformatted input, and store all the characters in the array, including whitespace characters.
Stop the loop when you reach the limit of the number of characters you can hold or the newline character is encountered.
cout << "Please enter a line of text" << endl;
// Read the characters one by one.
// Don't read more than 79 characters.
// Stop if a newline or EOF is encountered.
int c;
while ( x < 79 && (c = cin.get()) != '\n' && c != EOF )
{
thisArray[x] = c;
++x;
}
// null terminate the string.
thisArray[x] = '\0';
You have a couple issues in you code. First you are not inputting into the array in your do...while loop. You need to use the index operator([]) with the array name for that:
do{
cout << "Please enter a character" << endl;
cin >> thisArray[x];
x++; ^^^ input each character into the correct index.
} while (x < 80);
Secondly your for loop has the wrong condition.
for (x = 0; x <= thisArray[x]; x++)
Should be
for (x = 0; x < 80; x++)
Notice that I changed the <= to < as an array of size 80 has the elements of [0, 79]
Related
My program will repeat output: "You are currently on the 2 floor out of 5
The sum of the codes is: 7 and the product of the codes is: 12
Try again before he catches onto you!"
Based on how many wrong characters are added how can I fix this? I have inserted the cin.clear and cin.ignore but it will repeat the part above.
i.e. if I type wasds it will repeat 5x. Any other notes are also appreciated.
#include <iostream>
#include <ctime>
using namespace std;
int PlayerLevel = 0;
int MaxLevel = 5;
bool GamePlay ()
{
srand(time(NULL));
int PlayerGuessA, PlayerGuessB, PlayerGuessC;
int CodeA = rand() % PlayerLevel + PlayerLevel;
int CodeB = rand() % PlayerLevel + PlayerLevel;
int CodeC = rand() % PlayerLevel + PlayerLevel;
int SumofCodes = CodeA + CodeB + CodeC;
int ProductofCodes = CodeA * CodeB * CodeC;
cout << "You are currently on the " << PlayerLevel << " floor out of 5" << endl;
cout << "The sum of the codes is: " << SumofCodes << " and the product of the codes is: " << ProductofCodes << endl;
cin >> PlayerGuessA >> PlayerGuessB >> PlayerGuessC;
int PlayerProduct = PlayerGuessA * PlayerGuessB * PlayerGuessC;
int PlayerSum = PlayerGuessA + PlayerGuessB + PlayerGuessC;
if (PlayerProduct == ProductofCodes && SumofCodes == PlayerSum) {
cout << "Great Job you got this!!!\n" << endl;
++PlayerLevel;
return true;
}
else
{
cout << "Try again before he catches onto you!\n" << endl;
return false;
}
}
int GameStart()
{
string Introduction = "Welcome to your worst nightmare. You are trapped in a murderer's house. You are on the 5th floor and need to get to the first floor to escape.\n";
string Instructions = "He has each door locked behind a security system that requires a 3 number code to disarm it.\nEnter the codes and move foward. Each level will the code will be harder to figure out.\n";
string PlayerStart;
cout << Introduction << endl;
cout << Instructions << endl;
cout << "Would you like to escape? Yes or No" << endl;
cin >> PlayerStart;
if (!(PlayerStart != "Yes" && PlayerStart != "yes")) {
++PlayerLevel;
}
return 0;
}
int main ()
{
if (PlayerLevel == 0) {
GameStart();
}
while (PlayerLevel <= MaxLevel)
{
bool bLevelComplete = GamePlay();
cin.clear ();
cin.ignore();
}
cout << "You Made it out! Now run before he finds out!" << endl;
return 0;
}
When the type of the input doesn't match the type of the variable that it is being extracted to, cin sets the fail bit. Once this happens, all subsequent reads fail until the stream is reset. The offending characters are still left in the buffer, so that needs to be cleared out as well.
Your usage of cin.clear() and cin.ignore() meant that the fail bit was getting reset, but only one offending character was being removed (cin.ignore() ignores one character by default). This is why you saw the output repeating x times for x erroneous characters.
You could do something like this:
while (PlayerLevel <= MaxLevel)
{
bool bLevelComplete = GamePlay();
if (cin.fail())
{
//Input extraction failed, need to reset stream and clear buffer until newline
cin.clear();
cin.ignore(numeric_limits<streamsize>::max(),'\n');
}
}
This question already has answers here:
How to check if the input number integer not float?
(3 answers)
How to check if the input is a valid integer without any other chars?
(7 answers)
How to test whether stringstream operator>> has parsed a bad type and skip it
(5 answers)
Closed 4 years ago.
I am new to c++ - and I am having trouble to validate user that the input must be a integer, and I just want the basic - simpler way, for me to understand. (Just basic way) to validate the input of the user How can I make it to work prior to my code below. Thank you for you're help and you're time. For example: if I get prompt to enter positive number and Input the letter x that means it will show "Invalid entry".. thank you!
Here is my code:
Updated
if (cin >> x && x < 0) {
} else {
cout << "Invalid entry, Try again." << endl;
cin.clear();
while (cin.get() != '\n');
}
#include <iostream>
#include <fstream> // for file stream.
using namespace std;
int main() {
// Variables
int x, reversedNumber, remainder;
// Creating String variables and setting them to empty string.
string even = "", odd = "";
// Creating a file.
ofstream out;
out.open("outDataFile.txt");
// creating a character variable
// for the user input if they want to use the program again.
char ch;
do {
// Even number.
even = "";
// Odd number.
odd = "";
// Reversed number
reversedNumber = 0;
// Prompt the user to enter a positive integer.
cout << "\nEnter a positive integer and press <Enter> ";
// Validate user input.
while (cin >> x || x < 1) {
// Clear out the cin results.
cin.clear();
// Display user that it is not a positive integer.
cout << "Invalid entry, Try again. ";
}
// Display Results to the screen
cout << "the original number is " << x << "\n";
// Display results in the text file.
out << "the original number is " << x << "\n";
// Display number reversed.
cout << "the number reversed ";
// Display number reversed in text file.
out << "the number reversed ";
//Reversing the integer.
while (x != 0) {
remainder = x % 10;
reversedNumber = reversedNumber * 10 + remainder;
// Display on screen
cout << remainder << " ";
// Display in text file.
out << remainder << " ";
x /= 10;
}
// Display the results on screen and in the text file.
cout << "\n";
out << "\n";
// Reading the reverse numbers result.
while (reversedNumber != 0) {
remainder = reversedNumber % 10;
// Checking if the number is even or odd.
if (remainder % 2 == 0) {
// even = even * 10 + remainder;
} else {
// odd = odd * 10 + remainder;
}
reversedNumber /= 10;
}
//Displaying the even numbers.
if (even != "") {
cout << "the even digits are " << even << "\n";
out << "the even digits are " << even << "\n";
}
// If it is not even then display..
else {
cout << "There are no even digits \n";
out << "There are no even digits \n";
}
//Display the odd results.
if (odd != "") {
cout << "the odd digits are " << odd << "\n";
out << "the odd digits are " << odd << "\n";
}
// If its not odd then display.
else {
cout << "There are no odd digits \n";
out << "There are no odd digits \n";
}
// just a divider to divide the results inside text file.
out << "----------------- \n";
// Prompt the user if they want to use the program again.
cout << "\nDo you like to continue/repeat? (Y/N):";
// get the input from user.
cin >> ch;
if ((ch == 'Y') || (ch == 'y')) {
} else {
cout << "\nGoodbye!" << endl;
}
} while (ch == 'y' || ch == 'Y');
// close the text file.
out.close();
return 0;
}
You could read a string from cin and check each character to make sure that when passed to isdigit() it returns true.
std::string x;
std::cin >> x;
for(char c : x){ //for each char c in string x
if(!isdigit(c)) //Invalid
}
Why am I getting stuck in my validation loop after hitting Y to continue? I have to use cin.get and can not use strings
This program collects input from a user and displays them by using a pointer with an array, I have to validate for negative numbers, letters and newline characters with the appropriate message
#include <iostream>
#include <iomanip>
using namespace std;
void validateUserInput(char *userInputCharArray, int &strLength);
int const ARRAY_SIZE = 100;
int main()
{
char *userInputCharArray = nullptr;
char yes = NULL;
int lengthOfInput;
//creating a dynamic array size 100
userInputCharArray = new char[ARRAY_SIZE];
//loop
do
{
int count = 0;
//user prompt and accept input
cout << "Please enter an integer >= 0 and press <ENTER>: " << endl;
cin.get(userInputCharArray, ARRAY_SIZE);
while(userInputCharArray[count] != ' ' && userInputCharArray[count] != '\0')
count++;
{
if(userInputCharArray[count] == ' ')
{
userInputCharArray[count] = '\0';
}
}
lengthOfInput = count;
validateUserInput(userInputCharArray, lengthOfInput);
cout << "Your number is: " << endl;
for(int i = 0; i < lengthOfInput; i++)
{
cout << userInputCharArray[i] - '0' << " ";
}
cout << endl;
cout << "Press y to continue or any other button to exit: " <<endl;
cin >> yes;
delete [] userInputCharArray;
userInputCharArray = nullptr;
userInputCharArray = new char[ARRAY_SIZE];
}while(yes == 'y' || yes == 'Y');
cout << "Thank you Good-Bye";
cout << endl;
delete [] userInputCharArray;
userInputCharArray = nullptr;
system("pause");
return 0;
}
Im getting stuck in my functions while loop
void validateUserInput(char *userInputCharArray, int &strLength)
{
int counter = 0;
while(*userInputCharArray < '0' || (*userInputCharArray >= 'A' && *userInputCharArray <= 'Z')
|| (*userInputCharArray >= 'a' && *userInputCharArray <= 'z')
|| *userInputCharArray == 0)
{
cout << "Please enter a positive integer and press <ENTER>: " <<endl;
cin.get(userInputCharArray, ARRAY_SIZE);
}
while(userInputCharArray[counter] != ' ' && userInputCharArray[counter] != '\0')
counter++;
if(userInputCharArray[counter] == ' ')
{
userInputCharArray[counter] = '\0';
}
strLength = counter;
}
According to the while loop you have here, you will keep on calling in.get so long as the first character that you read in is a digit or an alphabetic character. So, if you start your input with one of those characters, you will loop forever.
I'd suggest that you get input a line at a time and then parse what you get.
cin.get(*userInputCharArray);
Will extract one character only, therefore the terminator character '\0' will not be part of userInputCharArray.
Change it to read a line at a time and parse the input. If you're still having issues, you can flush your input buffer before each read like so:
cin.ignore(10, "\n");
cin.get(userInputCharArray, ARRAY_SIZE);
I wrote a program for my computer science class that validates and solves sudoku puzzles from .txt files, but I wanted to take it one step further and write a program that made it easy to input and sudoku game. I'm sure you can figure out the format of the files based on this code. My only problem is that the last cin gets skipped, and that option is important to me. Any insight will be appreciated!!
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
struct s {
s();
~s() {/*zzzz*/}
void show_grid();
void set (int &r, int &c, int &v) {g[r][c] = v;}
private:
int g[9][9];
};
//************************************************************************
void s::show_grid() {
//print game out to check it
cout << " | ------------------------------- |" << endl;
for (int k=0; k<81; k++) {
if (k%3 == 0)
cout << " |";
cout << " " << g[k/9][k%9];
if (k%9 == 8) {
cout << " |" << endl;
if ((k/9)%3 == 2)
cout << " | ------------------------------- |" << endl;
}
}
cout << endl;
}
//************************************************************************
s::s() {
//initialize all elements to zero
for (int i=0; i<9; i++) {
for (int j=0; j<9; j++) {
g[i][j] = 0;
}
}
}
//************************************************************************
void create_name (string &name) {
//append .txt extension LIKE IT OR NOT
string ext = name;
ext.erase(ext.begin(), ext.end() - 4);
if (ext.compare(".txt")!=0)
name.append(".txt");
}
//************************************************************************
int main () {
s g;
string name;
string yon("");
int count = 0;
int row, col, val, rcv;
ofstream os;
cout << "Enter game file name: ";
cin >> name;
create_name(name);
//open and do typical checks
os.open(name.c_str());
if (os.fail()) {
cerr << "Could not create " << name << ". Waaaah waaaaaaaaaah...\n\n";
return 0;
}
//useful output (hopefully)
cout << "Enter grid coordinates and value as a 3-digit number,\n"
<< "from left to right, row by row.\n"
<< "(e.g. 2 in first box would be 112)\n";
//take input as one int, to be user friendly
while (cin >> rcv && count < 81) {
row = (rcv / 100) - 1;
col = ((rcv / 10) % 10) - 1;
val = rcv % 10;
os << row << " " << col << " " << val << endl;
g.set (row, col, val);
count++;
}
os.close();
//From here down is broken, but it still compiles, runs, and works
cout << "Show grid input(y/n)?\n";
cin >> yon;
if (yon.compare("y")==0)
g.show_grid();
else if (yon.compare("n")==0)
cout << "Peace!\n";
return 0;
}
The problem is here:
while (cin >> rcv && count < 81)
Consider what happens when count==81: First, rcv will be input from cin, and only then the condition count < 81 will be evaluated to false. The loop will stop, and the value of rcv will be ignored. So effectively you read one input too many.
You should change the order of evaluation, so that count is checked first:
while (count < 81 && cin >> rcv)
Edit:
According to your comment above you are actually expecting to read less than 81 values. In that case, I recommend having the user input a special value (for example, 0) to terminate the loop. You'd just need to add if (rcv==0) break;. If you just input an invalid value as you are apparently doing, the cin stream will be put in a failed state and further input will not succeed.
Try something like:
//useful output (hopefully)
cout << "Enter grid coordinates and value as a 3-digit number,\n"
<< "from left to right, row by row.\n"
<< "(e.g. 2 in first box would be 112)\n"
<< "or Z to end the loop\n"; // 1
//take input as one int, to be user friendly
while (count < 81 && cin >> rcv ) { // 2
row = (rcv / 100) - 1;
col = ((rcv / 10) % 10) - 1;
val = rcv % 10;
os << row << " " << col << " " << val << endl;
g.set (row, col, val);
count++;
}
if(!std::cin) { // 3
std::cin.clear();
std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
}
1) Let the user know that he can enter in invalid char. It doesn't have to be Z, actually any non-numeric char will work.
2) Fix off-by-one error in the order of the &&.
3) If std::cin is in error state, clear the error and ignore the Z.
cin >> yon
still actually reads in a variable, it just reads in the variable that the while loop found to be false. When the while loop condition returns false rcv is ignored, so the number remains in the input stream waiting for the next cin statement. When yon is called that number meant for rcv is read into yon, giving you some strange errors.
it would be better to use interjay's method:
while (count < 81 && cin >> rcv)
void offer_help();
bool play_one_game();
int main() {
offer_help();
play_one_game();
}
void offer_help() {
int help_response;
cout << "Need help? (0/1) ";
cin >> help_response;
if (help_response == 1)
cout << "I will generate a pattern of 4 numbers, each in the range 0 through 9.\n Each guess that you enter will be a line containing 4 integers,\n separated by spaces, such as:\n\t 2 4 7 1\n FOr each guess, I will echo back a lost consisting of\n 0's and 1's, with a 1 in a given position meaning that\n you guessed the number, and a zero meaning that you didn't.\n For example, if the actual solution was 2 3 6 1, I'll respond\n\t 1 0 0 1\n See how many guesses it takes you to get the solution!\n\n If you want to give up, type a negative number for one of\n your guesses, and we'll tell you what the pattern was.\n\n";
}
bool play_one_game() {
srand(time(0)); //needed to start randint
vector<int> solution; //vector of 4 randomly generated
//solutions
vector<int> guess; //vector containing user guesses.
vector<int> result;
int guess_input;
for(int i = 0; i < solution.size(); ++i)
solution[i] = randint(10);
int trial_number = 0; //int that shows what guess the user is on
while (play_one_game() == true) {
//ask user for inputs.
cout << "Guess #" << ++trial_number << "? ";
for (int i = 0; i < guess.size(); ++i){
cin >> guess_input;
guess.push_back(guess_input);
}
//outputs error if user inputs a letter.
if (!cin) {
cerr << "Bad input data! Feed me numbers!\n";
return 43;
}
if (cin < 0){
cout << "Too bad! Solution was " << endl;
for(int i = 0; i < result.size(); i++)
cout << (result[i]);
}
//determines if user correctly guessed any of the
//numbers and tells the user which is correct.
for (int i = 0; i < result.size(); i++) {
if (guess[i]==solution[i])
cout << 1 << " ";
else if (guess[i]!=solution[i])
cout << 0 << " ";
}
cout << endl;
// playagain();
cout << endl << "Play again (0/1)? ";
int replay;
cin >> replay;
if (replay == 0) {
play_one_game() == false;
return 5;
}
else if (replay == 1)
play_one_game() == true;
else {
cerr << "wat?\n";
return 10;
}
}
}
This is designed to allow a player to guess a pattern of random numbers.
No idea why I am getting a segmentation fault. The program is supposed to call the offer_help function, then the play_one_game function within main function. Then it should ask the player whether he wants to play again. If no, then bool play_one_game should be set to false and it should exit.
This is related to the play_one_game bool function.
You're getting a segmentation fault, because you end up in an endless recursion in the following line:
while (play_one_game() == true) {
play_one_game will call play_one_game in this line, and this will call play_one_game in the same line again. This will result in a stack overflow at last.
Better use some bool keepPlaying; and while(keepPlaying) instead.
EDIT: Well, this is a little bit more than a simple answer, but I like games, so... have a look at the following code:
#include <iostream>
#include <ctime>
#include <cstdlib>
#include <vector>
bool play_one_game();
void offer_help() {
int help_response;
std::cout << "Need help? (0/1) ";
std::cin >> help_response;
if (help_response == 1)
std::cout << "I will generate a pattern of 4 numbers, each in the range 0 through 9.\n"
"Each guess that you enter will be a line containing 4 integers,\n"
"separated by spaces, such as:\n"
"\t 2 4 7 1\n"
"For each guess, I will echo back a lost consisting of\n"
"0's and 1's, with a 1 in a given position meaning that\n"
"you guessed the number, and a zero meaning that you didn't.\n"
"For example, if the actual solution was 2 3 6 1, I'll respond\n"
"\t 1 0 0 1\n"
"See how many guesses it takes you to get the solution!\n\n"
"If you want to give up, type a negative number for one of\n"
"your guesses, and we'll tell you what the pattern was.\n\n";
}
int main() {
offer_help();
srand(time(0)); // Initialize random numbers with current time as seed
while(play_one_game()); // if play_one_game returns true, play again
}
bool play_one_game() {
std::vector<int> solution(4); // Four solutions for our guessing game
std::vector<int> guess; // User guesses
for(unsigned i = 0; i < solution.size(); ++i)
solution[i] = rand() % 10;
int trial_number = 0; //int that shows what guess the user is on
bool keepPlaying = true;
while(keepPlaying){
std::cout << "Guess #" << ++trial_number << "? ";
guess.clear(); // Clear old guesses
for(unsigned i = 0; i < solution.size(); ++i){
int guess_input;
//outputs error if user inputs a letter.
if (!(std::cin >> guess_input)) {
std::cerr << "Bad input data! Feed me numbers!\n";
std::cerr << "Try again!" << std::endl;
std::cin.clear(); // Clear flags
continue;
}
if (guess_input < 0){
std::cout << "Too bad! Solution was " << std::endl;
for(unsigned i = 0; i < solution.size(); i++)
std::cout << (solution[i]);
keepPlaying = false;
break;
}else
guess.push_back(guess_input);
}
if(!keepPlaying)
break;
if(solution.size() != guess.size()){
std::cerr << "Wrong number of guesses, try again!" << std::endl;
continue;
}
//determines if user correctly guessed any of the
//numbers and tells the user which is correct.
bool correct = true;
for (unsigned i = 0; i < solution.size(); i++) {
if (guess[i] == solution[i])
std::cout << 1 << " ";
else{
correct = false;
std::cout << 0 << " ";
}
}
if(correct){
std::cout << "Congratulations - you won!" << std::endl;
break;
}
std::cout << std::endl;
}
int replay = -1;
do{
// Ask user for input until input is 0 or 1
std::cout << std::endl << "Play again (0/1)? ";
std::cin >> replay;
}
while(replay != 0 && replay != 1);
return static_cast<bool>(replay); // return user replay answer (false/true)
}
Try to keep your code as simple as possible. Welcome to SO. And don't expect future answers to be that excessive.
You're never inserting anything into your solution vector. You just declare the vector, and then say:
for(int i = 0; i < solution.size(); ++i)
solution[i] = randint(10);
...which won't do anything since at this point solution.size() == 0. Later, when you iterate over your result vector, you end up accessing invalid elements in your empty solution vector. You also can't assume that the result vector and solution vector are the same size.