Use of stoi in C++

In this tutorial, we shall have a look at the use of stoi in C++.

stoi() in C++

stoi() is a function that takes a string as input and returns the integer values.

First Example of stoi function

#include <iostream>
#include <string> 
using namespace std;

int main() {

  string a = "500";
 
  
  int x = stoi(a);

  cout  << x << endl;
}

Output

500

Initially, 500 is declared in a string, upon using the stoi function, it is converted into an integer.

Example 2

#include <iostream>
#include <string> 
using namespace std;

int main() {

  string a = "10000 codespeedy";
 
  
  int x = stoi(a);

  cout  << x << endl;
}

Output

1000

Here 1000 codespeedy is declared as a string, later upon using the stoi function, it returns the integer values.

Example 3

#include <iostream>
#include <string> 
using namespace std;

int main() {

  string a = "8941.0987421";
 
  
  int x = stoi(a);

  cout  << x << endl;
}

Output

8941

in this example, we see that float value is declared as a string, by using stoi() function, it returns the integer values.

You can also read: C++ Pre-Processors