std::stoi missing in g++ 4.7.2?

Question

I get the error message \"stoi is not a member of std\" when I try to use std::stoi and try to compile it. I\'m using g++ 4.7.2 from the command line so it can\'t be IDE err

Answer 1

std::stoi() is new in C++11 so you have to make sure you compile it with:

g++ -std=c++11 example.cpp

or

g++ -std=c++0x example.cpp

Answer 2

For older version of C++ compiler does not support stoi. for the older version you can use the following code snippet to convert a string to integer.

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

int main() {
    string input;
    cin >> input;
    int s = std::atoi(input.c_str());
    cout<<s<<endl;
    return 0;
}