I am a c++ beginner and I am curious to why this does not work:
#include <iostream>
using namespace std;
int main ()
{
int firstname;
int lastname;
cout << "My name is " << firstname << lastname;
cin >> firstname >> lastname;
cout << endl;
return 0;
}
I want the output to simply be where the user inputs their first name and the last name and it turns out to be as follows:
Example:
My name is John Doe.
#include <string>
...
string firstname;
string lastname;
int values hold numbers. To store names, use strings.
cin >> firstname >> lastname;
cout << "My name is " << firstname << " " << lastname;
Then make sure to read the names before you print them. The cin and cout should be swapped. I've also added a space (" ") in the printout between the two variables.
#include <iostream>
#include <string> // so you can use string
using namespace std;
int main() {
string first;
string last;
cin >> first;
cin >> last; // getting input from using and storing it in last
cout << "My name is " << first << last << endl; // printing out "My name is and " and what you wrote for first and last
return 0;
}
cout << "My name is ";
cin >> firstname >> lastname;
cout << firstname << " " << lastname;
This should output a single line of:
My name is John Doe
Plus, strings of characters are stored in string types, not int types
So you'd have to include <string>, and change the ints to string
Name can be of int type change it to std::string
Here is the modified code will produce output as you want.
#include <iostream>
int main ()
{
std::string firstname;
std::string lastname;
std::cin >> firstname >> lastname;
std::cout << "My name is " << firstname<<" " << lastname<<"\n";
return 0;
}
Note that the you will have to add " " while printing if you want a white space between your first name and last name.
Try to take input using 'getline(cin,str); if your string contain white space too.
I would suggest you to not to use standard namespace i.e. using namespace std; while writing the code. For more detail please have a look of link provided below
Why is "using namespace std" considered bad practice?
First I would try to prompt the user to enter their first and last name. Or else how would they know what to enter? And using int type does not help at all because the user would be entering a string and not an integer. Try this ...
#include <iostream>
using namespace std;
int main() {
cout << "Pleas enter your first and last name." << endl;
string name;
cin >> name;
cout << "Hello " << name << endl;
return 0;
}
Make sure that the user knows what to input (first and last name) otherwise they will not know what to input. This is the output code you can use:
cout << "Please enter your first and last name." << endl;
So the full code should look something like this:
#include <iostream>
#include <string>
using namespace std;
int main ()
{
string firstname;
string lastname;
cout << "Please enter your first and last name: " << endl;
cin >> firstname >> lastname;
cout << "My name is " << firstname << " " << lastname;
cout << endl;
return 0;
}
You are doing
int firstname;
int lastname;
meaning that you want to get an integer value, however you want a string. So, replace the int with std::string or string in your case. Also, remember to #include <string> to get the string functionality. After doing this, you should be able to input and return letters. :D
#include <iostream>
#include <string>
using namespace std;
int main ()
{
string firstname;
string lastname;
cout << "My name is " << firstname << lastname;
cin >> firstname >> lastname;
cout << endl;
return 0;
}
Might I add that you generally should not use using namespace std; as it is considered bad practice, it also is not really necessary, you could just type std::.... using namespace std is used if you do not want to type the namespace name every time, but it's generally better to distinguish between which type of functions you want to use with the same names but in different namspaces. and using '\n' for a new line as well instead of endl. This is because endl takes more time to complete than \n.
I recommend to also include the namespace in your code if you are a beginner. In simple cases like printing strings its readable but a better practice if you're learning to include std::string, std::cin, and std::cout. In this case the :: just means to grab the keyword(right value) from its namespace(left value).
Related
#include <string>
std::string input;
std::cin >> input;
The user wants to enter "Hello World". But cin fails at the space between the two words. How can I make cin take in the whole of Hello World?
I'm actually doing this with structs and cin.getline doesn't seem to work. Here's my code:
struct cd
{
std::string CDTitle[50];
std::string Artist[50];
int number_of_songs[50];
};
std::cin.getline(library.number_of_songs[libNumber], 250);
This yields an error. Any ideas?
It doesn't "fail"; it just stops reading. It sees a lexical token as a "string".
Use std::getline:
#include <string>
#include <iostream>
int main()
{
std::string name, title;
std::cout << "Enter your name: ";
std::getline(std::cin, name);
std::cout << "Enter your favourite movie: ";
std::getline(std::cin, title);
std::cout << name << "'s favourite movie is " << title;
}
Note that this is not the same as std::istream::getline, which works with C-style char buffers rather than std::strings.
Update
Your edited question bears little resemblance to the original.
You were trying to getline into an int, not a string or character buffer. The formatting operations of streams only work with operator<< and operator>>. Either use one of them (and tweak accordingly for multi-word input), or use getline and lexically convert to int after-the-fact.
You have to use cin.getline():
char input[100];
cin.getline(input,sizeof(input));
The Standard Library provides an input function called ws, which consumes whitespace from an input stream. You can use it like this:
std::string s;
std::getline(std::cin >> std::ws, s);
Use :
getline(cin, input);
the function can be found in
#include <string>
You want to use the .getline function in cin.
#include <iostream>
using namespace std;
int main () {
char name[256], title[256];
cout << "Enter your name: ";
cin.getline (name,256);
cout << "Enter your favourite movie: ";
cin.getline (title,256);
cout << name << "'s favourite movie is " << title;
return 0;
}
Took the example from here. Check it out for more info and examples.
How do I read a string from input?
You can read a single, whitespace terminated word with std::cin like this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a word:\n";
string s;
cin>>s;
cout << "You entered " << s << '\n';
}
Note that there is no explicit memory management and no fixed-sized buffer that you could possibly overflow.
If you really need a whole line (and not just a single word) you can do this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a line:\n";
string s;
getline(cin,s);
cout << "You entered " << s << '\n';
}
THE C WAY
You can use gets function found in cstdio(stdio.h in c):
#include<cstdio>
int main(){
char name[256];
gets(name); // for input
puts(name);// for printing
}
THE C++ WAY
gets is removed in c++11.
[Recommended]:You can use getline(cin,name) which is in string.h
or cin.getline(name,256) which is in iostream itself.
#include<iostream>
#include<string>
using namespace std;
int main(){
char name1[256];
string name2;
cin.getline(name1,256); // for input
getline(cin,name2); // for input
cout<<name1<<"\n"<<name2;// for printing
}
I rather use the following method to get the input:
#include <iostream>
#include <string>
using namespace std;
int main(void) {
string name;
cout << "Hello, Input your name please: ";
getline(cin, name);
return 0;
}
It's actually super easy to use rather than defining the total length of array for a string which contains a space character.
#include <string>
std::string input;
std::cin >> input;
The user wants to enter "Hello World". But cin fails at the space between the two words. How can I make cin take in the whole of Hello World?
I'm actually doing this with structs and cin.getline doesn't seem to work. Here's my code:
struct cd
{
std::string CDTitle[50];
std::string Artist[50];
int number_of_songs[50];
};
std::cin.getline(library.number_of_songs[libNumber], 250);
This yields an error. Any ideas?
It doesn't "fail"; it just stops reading. It sees a lexical token as a "string".
Use std::getline:
#include <string>
#include <iostream>
int main()
{
std::string name, title;
std::cout << "Enter your name: ";
std::getline(std::cin, name);
std::cout << "Enter your favourite movie: ";
std::getline(std::cin, title);
std::cout << name << "'s favourite movie is " << title;
}
Note that this is not the same as std::istream::getline, which works with C-style char buffers rather than std::strings.
Update
Your edited question bears little resemblance to the original.
You were trying to getline into an int, not a string or character buffer. The formatting operations of streams only work with operator<< and operator>>. Either use one of them (and tweak accordingly for multi-word input), or use getline and lexically convert to int after-the-fact.
You have to use cin.getline():
char input[100];
cin.getline(input,sizeof(input));
The Standard Library provides an input function called ws, which consumes whitespace from an input stream. You can use it like this:
std::string s;
std::getline(std::cin >> std::ws, s);
Use :
getline(cin, input);
the function can be found in
#include <string>
You want to use the .getline function in cin.
#include <iostream>
using namespace std;
int main () {
char name[256], title[256];
cout << "Enter your name: ";
cin.getline (name,256);
cout << "Enter your favourite movie: ";
cin.getline (title,256);
cout << name << "'s favourite movie is " << title;
return 0;
}
Took the example from here. Check it out for more info and examples.
How do I read a string from input?
You can read a single, whitespace terminated word with std::cin like this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a word:\n";
string s;
cin>>s;
cout << "You entered " << s << '\n';
}
Note that there is no explicit memory management and no fixed-sized buffer that you could possibly overflow.
If you really need a whole line (and not just a single word) you can do this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a line:\n";
string s;
getline(cin,s);
cout << "You entered " << s << '\n';
}
THE C WAY
You can use gets function found in cstdio(stdio.h in c):
#include<cstdio>
int main(){
char name[256];
gets(name); // for input
puts(name);// for printing
}
THE C++ WAY
gets is removed in c++11.
[Recommended]:You can use getline(cin,name) which is in string.h
or cin.getline(name,256) which is in iostream itself.
#include<iostream>
#include<string>
using namespace std;
int main(){
char name1[256];
string name2;
cin.getline(name1,256); // for input
getline(cin,name2); // for input
cout<<name1<<"\n"<<name2;// for printing
}
I rather use the following method to get the input:
#include <iostream>
#include <string>
using namespace std;
int main(void) {
string name;
cout << "Hello, Input your name please: ";
getline(cin, name);
return 0;
}
It's actually super easy to use rather than defining the total length of array for a string which contains a space character.
#include <string>
std::string input;
std::cin >> input;
The user wants to enter "Hello World". But cin fails at the space between the two words. How can I make cin take in the whole of Hello World?
I'm actually doing this with structs and cin.getline doesn't seem to work. Here's my code:
struct cd
{
std::string CDTitle[50];
std::string Artist[50];
int number_of_songs[50];
};
std::cin.getline(library.number_of_songs[libNumber], 250);
This yields an error. Any ideas?
It doesn't "fail"; it just stops reading. It sees a lexical token as a "string".
Use std::getline:
#include <string>
#include <iostream>
int main()
{
std::string name, title;
std::cout << "Enter your name: ";
std::getline(std::cin, name);
std::cout << "Enter your favourite movie: ";
std::getline(std::cin, title);
std::cout << name << "'s favourite movie is " << title;
}
Note that this is not the same as std::istream::getline, which works with C-style char buffers rather than std::strings.
Update
Your edited question bears little resemblance to the original.
You were trying to getline into an int, not a string or character buffer. The formatting operations of streams only work with operator<< and operator>>. Either use one of them (and tweak accordingly for multi-word input), or use getline and lexically convert to int after-the-fact.
You have to use cin.getline():
char input[100];
cin.getline(input,sizeof(input));
The Standard Library provides an input function called ws, which consumes whitespace from an input stream. You can use it like this:
std::string s;
std::getline(std::cin >> std::ws, s);
Use :
getline(cin, input);
the function can be found in
#include <string>
You want to use the .getline function in cin.
#include <iostream>
using namespace std;
int main () {
char name[256], title[256];
cout << "Enter your name: ";
cin.getline (name,256);
cout << "Enter your favourite movie: ";
cin.getline (title,256);
cout << name << "'s favourite movie is " << title;
return 0;
}
Took the example from here. Check it out for more info and examples.
How do I read a string from input?
You can read a single, whitespace terminated word with std::cin like this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a word:\n";
string s;
cin>>s;
cout << "You entered " << s << '\n';
}
Note that there is no explicit memory management and no fixed-sized buffer that you could possibly overflow.
If you really need a whole line (and not just a single word) you can do this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a line:\n";
string s;
getline(cin,s);
cout << "You entered " << s << '\n';
}
THE C WAY
You can use gets function found in cstdio(stdio.h in c):
#include<cstdio>
int main(){
char name[256];
gets(name); // for input
puts(name);// for printing
}
THE C++ WAY
gets is removed in c++11.
[Recommended]:You can use getline(cin,name) which is in string.h
or cin.getline(name,256) which is in iostream itself.
#include<iostream>
#include<string>
using namespace std;
int main(){
char name1[256];
string name2;
cin.getline(name1,256); // for input
getline(cin,name2); // for input
cout<<name1<<"\n"<<name2;// for printing
}
I rather use the following method to get the input:
#include <iostream>
#include <string>
using namespace std;
int main(void) {
string name;
cout << "Hello, Input your name please: ";
getline(cin, name);
return 0;
}
It's actually super easy to use rather than defining the total length of array for a string which contains a space character.
#include <string>
std::string input;
std::cin >> input;
The user wants to enter "Hello World". But cin fails at the space between the two words. How can I make cin take in the whole of Hello World?
I'm actually doing this with structs and cin.getline doesn't seem to work. Here's my code:
struct cd
{
std::string CDTitle[50];
std::string Artist[50];
int number_of_songs[50];
};
std::cin.getline(library.number_of_songs[libNumber], 250);
This yields an error. Any ideas?
It doesn't "fail"; it just stops reading. It sees a lexical token as a "string".
Use std::getline:
#include <string>
#include <iostream>
int main()
{
std::string name, title;
std::cout << "Enter your name: ";
std::getline(std::cin, name);
std::cout << "Enter your favourite movie: ";
std::getline(std::cin, title);
std::cout << name << "'s favourite movie is " << title;
}
Note that this is not the same as std::istream::getline, which works with C-style char buffers rather than std::strings.
Update
Your edited question bears little resemblance to the original.
You were trying to getline into an int, not a string or character buffer. The formatting operations of streams only work with operator<< and operator>>. Either use one of them (and tweak accordingly for multi-word input), or use getline and lexically convert to int after-the-fact.
You have to use cin.getline():
char input[100];
cin.getline(input,sizeof(input));
The Standard Library provides an input function called ws, which consumes whitespace from an input stream. You can use it like this:
std::string s;
std::getline(std::cin >> std::ws, s);
Use :
getline(cin, input);
the function can be found in
#include <string>
You want to use the .getline function in cin.
#include <iostream>
using namespace std;
int main () {
char name[256], title[256];
cout << "Enter your name: ";
cin.getline (name,256);
cout << "Enter your favourite movie: ";
cin.getline (title,256);
cout << name << "'s favourite movie is " << title;
return 0;
}
Took the example from here. Check it out for more info and examples.
How do I read a string from input?
You can read a single, whitespace terminated word with std::cin like this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a word:\n";
string s;
cin>>s;
cout << "You entered " << s << '\n';
}
Note that there is no explicit memory management and no fixed-sized buffer that you could possibly overflow.
If you really need a whole line (and not just a single word) you can do this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a line:\n";
string s;
getline(cin,s);
cout << "You entered " << s << '\n';
}
THE C WAY
You can use gets function found in cstdio(stdio.h in c):
#include<cstdio>
int main(){
char name[256];
gets(name); // for input
puts(name);// for printing
}
THE C++ WAY
gets is removed in c++11.
[Recommended]:You can use getline(cin,name) which is in string.h
or cin.getline(name,256) which is in iostream itself.
#include<iostream>
#include<string>
using namespace std;
int main(){
char name1[256];
string name2;
cin.getline(name1,256); // for input
getline(cin,name2); // for input
cout<<name1<<"\n"<<name2;// for printing
}
I rather use the following method to get the input:
#include <iostream>
#include <string>
using namespace std;
int main(void) {
string name;
cout << "Hello, Input your name please: ";
getline(cin, name);
return 0;
}
It's actually super easy to use rather than defining the total length of array for a string which contains a space character.
#include <string>
std::string input;
std::cin >> input;
The user wants to enter "Hello World". But cin fails at the space between the two words. How can I make cin take in the whole of Hello World?
I'm actually doing this with structs and cin.getline doesn't seem to work. Here's my code:
struct cd
{
std::string CDTitle[50];
std::string Artist[50];
int number_of_songs[50];
};
std::cin.getline(library.number_of_songs[libNumber], 250);
This yields an error. Any ideas?
It doesn't "fail"; it just stops reading. It sees a lexical token as a "string".
Use std::getline:
#include <string>
#include <iostream>
int main()
{
std::string name, title;
std::cout << "Enter your name: ";
std::getline(std::cin, name);
std::cout << "Enter your favourite movie: ";
std::getline(std::cin, title);
std::cout << name << "'s favourite movie is " << title;
}
Note that this is not the same as std::istream::getline, which works with C-style char buffers rather than std::strings.
Update
Your edited question bears little resemblance to the original.
You were trying to getline into an int, not a string or character buffer. The formatting operations of streams only work with operator<< and operator>>. Either use one of them (and tweak accordingly for multi-word input), or use getline and lexically convert to int after-the-fact.
You have to use cin.getline():
char input[100];
cin.getline(input,sizeof(input));
The Standard Library provides an input function called ws, which consumes whitespace from an input stream. You can use it like this:
std::string s;
std::getline(std::cin >> std::ws, s);
Use :
getline(cin, input);
the function can be found in
#include <string>
You want to use the .getline function in cin.
#include <iostream>
using namespace std;
int main () {
char name[256], title[256];
cout << "Enter your name: ";
cin.getline (name,256);
cout << "Enter your favourite movie: ";
cin.getline (title,256);
cout << name << "'s favourite movie is " << title;
return 0;
}
Took the example from here. Check it out for more info and examples.
How do I read a string from input?
You can read a single, whitespace terminated word with std::cin like this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a word:\n";
string s;
cin>>s;
cout << "You entered " << s << '\n';
}
Note that there is no explicit memory management and no fixed-sized buffer that you could possibly overflow.
If you really need a whole line (and not just a single word) you can do this:
#include<iostream>
#include<string>
using namespace std;
int main()
{
cout << "Please enter a line:\n";
string s;
getline(cin,s);
cout << "You entered " << s << '\n';
}
THE C WAY
You can use gets function found in cstdio(stdio.h in c):
#include<cstdio>
int main(){
char name[256];
gets(name); // for input
puts(name);// for printing
}
THE C++ WAY
gets is removed in c++11.
[Recommended]:You can use getline(cin,name) which is in string.h
or cin.getline(name,256) which is in iostream itself.
#include<iostream>
#include<string>
using namespace std;
int main(){
char name1[256];
string name2;
cin.getline(name1,256); // for input
getline(cin,name2); // for input
cout<<name1<<"\n"<<name2;// for printing
}
I rather use the following method to get the input:
#include <iostream>
#include <string>
using namespace std;
int main(void) {
string name;
cout << "Hello, Input your name please: ";
getline(cin, name);
return 0;
}
It's actually super easy to use rather than defining the total length of array for a string which contains a space character.