When I run my code it display random symbols at the end - c++

I am separating a string into words and when I run the source code, it works but at the end it displays random symbols and letter.
#include <iostream>
#include <cstring>
#include <cctype>
using namespace std;
void seperatestring(string str);
int main()
{
string str;
cout << "Enter a string: ";
getline(cin, str);
seperatestring(str);
return 0;
}
void seperatestring(string str)
{
string word = "";
for (int i = 0; i < str[str.size()-1] ; i++)
{
if (str[i] == ' ')
{
cout << word << endl;
word = "";
}
else {
word = word + str[i];
}
}
cout << word << endl;
}
This is the source code. The only problem is that at the end of the result there are random symbols and letters. What should I fix in my source code to remove the random symbols at the end?

this looks suspicious:
for (int i = 0; i < str[str.size()-1] ; i++)
Don't you really mean:
for (int i = 0; i < str.size(); i++)

Related

How to read more than one line of input?

So I have built a small basic data encrypter (for learning purposes only). It is working perfectly fine but it reads only a single line of input. Is it my Editor problem or my code have some issues.
ps: I use CodeBlocks
#include <iostream>
#include <ctype.h>
using namespace std;
int main()
{
std::string str;
char enc;
int word;
cout << "\t\t\t\t\t\t\t\tENCRYPTOR" <<endl;
cout << "\t\t\t\t\t\t\t\t---------" <<endl;
cout << "Enter a Word: ";
getline(cin, str);
int n = 0;
cout << "\n\n\t\t\t\t\t\t\t\tENCRYPTED D#T#" <<endl;
cout << "\t\t\t\t\t\t\t\t--------------\n\n" << endl;
for(int i = 0; i < str.length(); i++){
int randomAdd[5] = {5,6,2,3,2};
int size = sizeof(randomAdd)/sizeof(randomAdd[0]);
// for(int j = 0; j < 5; j++){
word = str.at(i);
if(i%5 == 0){
n = 0;
}
enc = int(word) + randomAdd[n];
std::cout << char(enc);
n++;
}
return 0;
}
This works
Hello World
But I cannot enter this
Hello World
Have a nice day
because then the program exits command prompt without any error or message.
How can I read more than one line?
You can do as
#include <iostream>
using namespace std;
int main() {
string str;
while (getline(cin, str)) {
cout << str << endl;
}
return 0;
}
This code sample allows you to input multiple lines interactively from the command line/shell
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
using namespace std;
int main()
{
string str;
char enc;
int word;
vector<string> myInput;
cout << "\t\t\t\t\t\t\t\tENCRYPTOR" <<endl;
cout << "\t\t\t\t\t\t\t\t---------" <<endl;
while (str != "Enigma")
{
cout << "Enter a line (Write Enigma to exit input): ";
getline(cin, str);
myInput.push_back(str);
}
int n = 0;
cout << "\n\n\t\t\t\t\t\t\t\tENCRYPTED D#T#" <<endl;
cout << "\t\t\t\t\t\t\t\t--------------\n\n" << endl;
for(auto & myInputLine : myInput)
{
str = myInputLine;
for (size_t i = 0; i < str.length(); i++) {
int randomAdd[5] = { 5,6,2,3,2 };
int size = sizeof(randomAdd) / sizeof(randomAdd[0]);
word = str.at(i);
if (i % 5 == 0) {
n = 0;
}
enc = int(word) + randomAdd[n];
std::cout << char(enc);
n++;
}
}
return 0;
}
The input is finished if Enigma is written.
All input is stored in the vector container of the STL, see vector.
Afterwards, all the lines are encrypted by your algorithm.
Hope it helps?

Stuck on removing whitespace from string without using any helper code c++

Create a program titled str_compress.cpp. This program will take a sentence input and remove all spaces from the sentence. (A good first step in encryption programs) Make sure that both the input and output strings are all stored in a single variable each. Do not use numbers or symbols. Include both upper-case and lower-case letters. Account for cases with multiple spaces anywhere.
This is what I have so far:
#include <iostream>
#include <string>
using namespace std;
int main()
{
int i = 0, j = 0, len;
string str;
cout << "Enter string: ";
getline(cin, str);
len = str.length();
for (i = 0; i < len; i++)
{
if (str[i] == ' ')
{
for (j = i; j < len; j++)
{
str[j] = str[j + 1];
}
len--;
}
}
cout << str << endl;
system("pause");
return 0;
}
I can eliminate spaces, but only one at a time. If I copy and paste the for loop, I can remove all spaces for how many loops there are. I'm thinking that I can loop the for loop over and over until all spaces are gone, but I'm not sure how to do that. Also, I can't use anything like remove_all() or erase().
This is a strong clue for how the authors of your exercise want you to write your code:
Make sure that both the input and output strings are all stored in a single variable each
You should make a new string:
string new_str;
Use your loop over the input string. For each char in the string, check whether it is a space. If yes, do nothing. If no, append it to the output string:
for (i = ...)
{
char c = str[i];
if (c != ' ')
new_str.push_back(c);
}
Your loop's logic when removing a space is wrong. For instance, after removing a space, you then skip the next char in the string, which may be another space. Also, although you are decrementing the len, you don't resize the string to the new len before printing the new str value.
It should look more like this:
#include <iostream>
#include <string>
using namespace std;
int main()
{
size_t i, j, len;
string str;
cout << "Enter string: ";
getline(cin, str);
len = str.length();
i = 0;
while (i < len)
{
if (str[i] == ' ')
{
for (j = i + 1; j < len; ++j)
{
str[j - 1] = str[j];
}
--len;
}
else
++i;
}
str.resize(len);
cout << str << endl;
/* or, if you are not allowed to use resize():
cout.write(str.c_str(), len);
cout << endl;
*/
/* or, if you are not allowed to use write():
if (len < str.length())
str[len] = '\0';
cout << str.c_str() << endl;
*/
system("pause");
return 0;
}
Live Demo
However, your instructions do say to "Make sure that both the input and output strings are all stored in a single variable each", which implies that separate std::string variables should be used for input and output, eg:
#include <iostream>
#include <string>
using namespace std;
int main()
{
size_t i, j, len;
string str, str2;
cout << "Enter string: ";
getline(cin, str);
str2 = str;
len = str2.length();
i = 0;
while (i < len)
{
if (str2[i] == ' ')
{
for (j = i + 1; j < len; ++j)
{
str2[j - 1] = str2[j];
}
--len;
}
else
++i;
}
str2.resize(len);
cout << str2 << endl;
/* or:
cout.write(str2.c_str(), len);
cout << endl;
*/
/* or:
if (len < str2.length())
str2[len] = '\0';
cout << str2.c_str() << endl;
*/
system("pause");
return 0;
}
Live Demo
Alternatively:
#include <iostream>
#include <string>
using namespace std;
int main()
{
size_t i, j, len;
string str, str2;
cout << "Enter string: ";
getline(cin, str);
len = str.length();
str2.reserve(len);
for(i = 0; i < len; ++i)
{
char ch = str[i];
if (ch != ' ')
str2 += ch;
}
cout << str2 << endl;
system("pause");
return 0;
}
Live Demo
This is what worked for me. Thank you everyone for the help!!
int main()
{
int i, j, len;
string str, str2;
cout << "Enter string: ";
getline(cin, str);
len = str.length();
for (i = 0; i < len; ++i)
{
char ch = str[i];
if (ch != ' ')
str2 += ch;
}
cout << str2 << endl;
system("pause");
return 0;
}

s.erase is not working when trying to remove spaces from a string

I am trying to remove the spaces from a string to validate a Palindrome phrase. I have looked up other methods, but my professor literally copy and pasted the remove space for loop in our instructions but I can't get it to work and he says he doesn't want us going to the internet for help. I am trying to remove spaces from a phrase like "too hot to hoot" to validate it. I can get my program to work with single words like "bob", but not phrases.
#include <iostream>
#include <cstring>
using namespace std;
int main()
{
char input[100];
cout << "Please enter a word/phrase: ";
cin >> input;
for (int i = 0; i < strlen(input); i++)
{
while (s[i] == ' ')//getting "s" is undefined error
s.erase(i,1);
}
int i = 0;
int j = strlen(input)-1;
bool a = true;
for (i = 0; i < j; i++)
{
if (input[i] != input[j])
{
a = false;
}
j--;
}
if(a)
{
cout << input << " is a Valid Palindrome." << endl;
}
else
{
cout<< input << " is not a Valid Palindrome." << endl;
}
system("pause");
return 0;
}
Maybe you have not copy the result from temporary variable 's'. So, the modified codes should be:
#include <iostream>
#include <stdio.h>
#include <string.h>
#include <cstring>
using namespace std;
int main(int argc, char *argv[])
{
char input[100];
cout << "Please enter a word/phrase: ";
fgets(input, 100, stdin);
string s(input); // define a temporary variable 's'
int i = 0;
while (i < s.length())
{
if (s[i] == ' ' || s[i] == '\n')
{
s.erase(i, 1); // erase from variable 's', other then 'input'
continue;
}
i++;
}
// copy result from 's' to 'input'
sprintf(input, "%s", s.c_str());
int j = strlen(input) - 1;
bool a = true;
i = 0;
for (i = 0; i < j; i++)
{
if (input[i] != input[j])
{
a = false;
}
j--;
}
if (a)
{
cout << input << " is a Valid Palindrome." << endl;
}
else
{
cout << input << " is not a Valid Palindrome." << endl;
}
system("pause");
return 0;
}

How to move word in a circular motion in a string?

I have a string that contains X words (between each word there is a space) I have to move the words in a circular motion to the left according to the number that the user inserts. For example:
"hi my name is aviv and",
the user entered 2. "name is aviv and hi my" I'm looking for legality that repeats itself but I can not find.
Thanks for the guidance. Most importantly, I can not use built-in libraries
Update:
I see there are examples with libraries, I can not use any library.
So what I've done so far.
I wrote a function that gets a string and a number from the user, to move left.
Before sending the string to the function I try to calculate the number of characters I need to move.
My output is - "name is avivhi my"
Regarding the function:
When it gets a string without spaces it works great.
This is my code:
int main()
{
char str[] = "hi my name is aviv";
char str2[] = "hi my name is aviv";
int CountSpace = 0, CountWord = 0;
int Size = 18, flag = 0;
int MoveLeft, Index = 0;
for (int i = 0; str[i] != '\0'; i++)
{
if (str[i] == ' ')
{
CountSpace++;
}
}
CountWord = CountSpace + 1;//Understand how many words there are in a string.
cin >> MoveLeft;
if (MoveLeft >= CountWord)//
{
MoveLeft = (MoveLeft - ((MoveLeft / CountWord) * CountWord));//the size of movment;//To reduce the amount of moves if there is such a possibility
}
for (int i = Size - 1; i >= 0; i--)
{
if (str[i] == ' ')
{
flag++;
}
if (flag == MoveLeft)
{
Index = Size - 1 - (i + 1);//That's the amount of characters I have to move
break;
}
}
MoveLeft = Index;
//This code belongs to the function that accepts a string and the amount to move the characters
for (int i = 0; i < Size; i++)
{
if (i + MoveLeft < Size)
{
str[i] = str2[i + MoveLeft];
}
else
{
str[i] = str2[(i + MoveLeft) - Size];
}
}
cout << "Move Left: " << MoveLeft << endl << str << endl << str2 << endl;
return 0;
}
Here's a hint:
vector<string> words = Your_Code_To_Split_Input_Into_Words();
int count = words.size();
int shift = Your_Code_To_Read_Users_Input();
// print the sentence with the rotation specified by shift
for (int i = 0; i < count; i++)
{
int shifted_index = (i + shift) % count; // modulo math implements circular rotation
string spacing = (i == 0) ? "" : " "; // add a space before each word, except first word
cout << spacing << words[shifted_index];
}
cout << endl;
One possible answer, i highly recommend using vectors instead of regular arrays, it's easy and more dynamic, but i didn't use it because you said you can't use built-in libraries.
#include <iostream>
#include<string>
using namespace std;
int main() {
string a[10000];
int counter = 0;
string b = "hi my name is aviv and";
string temp = "";
int userNum = 2;
for(int i=0;i<b.length() ; i++){
if(b[i]!=' '){
temp+=b[i];
}
else if(b[i]==' ' && temp.length()){
a[counter]= temp;
temp = "";
counter++;
}
}
if(temp.length()){
a[counter] = temp;
}
for(int i=userNum;i<=counter+userNum;i++){
cout<<a[i%(counter+1)]<<endl;
}
}
If you can make use of std::rotate() from <algorithm>, this is much easy to do with that. Parse the words using std::stringstream and store to std::vector. Then apply the shif directly to the vector.
Sample Output: https://www.ideone.com/rSPhPR
#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <sstream>
int main()
{
std::vector<std::string> vec;
std::string str = "hi my name is aviv and";
std::string word;
std::stringstream sstr(str);
while(std::getline(sstr, word,' '))
vec.emplace_back(word);
int shift;
std::cout << "Enter the Shift: ";
std::cin >> shift;
std::rotate(vec.begin(), vec.begin() + shift, vec.end());
for(const auto& it: vec)
std::cout << it << " ";
return 0;
}
Here's a snippet :
#include <iostream>
#include <string>
#include <sstream>
using namespace std;
#define MaxWords 10
int main()
{
stringstream ss;
ss.str("hi my name is aviv and");
string str[MaxWords];
int i;
for (i =0; std::getline(ss, str[i],' ');i++ )
{
cout << str[i] << " ";
}
int n;
cout << "\nEnter pos to split : ";
cin >> n;
for (int j = n; j <= i; j++)
{
cout << str[j] << " ";
}
for (int j = 0; j < n; j++)
{
cout << str[j] << " ";
}
cout << endl;
return 0;
}
Output:

Unexpected cin behavior

I am writing a function int count_words(string str) that returns a count of all of the words in the string.
The issue is that regardless of the input, the result is 1. Can anyone help?
#include <iostream>
#include <string>
using namespace std;
int count_words(string str)
{
int i,j;
j = 1;
int l = str.length();
for(i = 0; i < l; i++)
{
string c = str.substr(i,1);
if(c == " ")
{
j++;
}
}
cout << "The total word in the string: " << j << endl;
return j;
}
int main()
{
string str;
cout << "Please enter a string: ";
cin >> str;
int result = count_words(str);
return 0;
}
You should use cin.getline if your string contains spaces, as using the >> operator with cin only reads up to the next whitespace
See std::cin input with spaces?
Consider iterating over the string:
auto cstyle= str.c_str();
for (int i = 0; i < str.length(); ++i)
{
if (cstyle[i]==' ')//assumes words are delimited by a single space
{
j++;
}
}
You should use: cin.getline, for example:
int main()
{
cout << "Please enter a string: ";
unsigned size=10;
char*chr=new char[size];
cin.getline(chr,size);
string str(chr);
//cin >> str;
int result = count_words(str);
return 0;
}