Convert String to Integer

Convert String to Integer in C++ (5 Programs)

BeginnerTopic: String Conversion Programs
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C++ Convert String to Integer Program

This program helps you to learn the fundamental structure and syntax of C++ programming.

Try This Code
#include <iostream>
#include <string>
#include <sstream>
using namespace std;

int main() {
    string str = "12345";
    
    // Method 1: Using stoi()
    int num1 = stoi(str);
    
    // Method 2: Using stringstream
    stringstream ss(str);
    int num2;
    ss >> num2;
    
    cout << "String: " << str << endl;
    cout << "Integer (method 1): " << num1 << endl;
    cout << "Integer (method 2): " << num2 << endl;
    
    return 0;
}
Output
String: 12345
Integer (method 1): 12345
Integer (method 2): 12345

Understanding Convert String to Integer

This program demonstrates 5 different methods to convert a string to an integer: using stoi(), stringstream, atoi(), sscanf(), and manual conversion.

Note: To write and run C++ programs, you need to set up the local environment on your computer. Refer to the complete article Setting up C++ Development Environment. If you do not want to set up the local environment on your computer, you can also use online IDE to write and run your C++ programs.

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