Convert Double to Int

Convert Double to Int in C++ (5 Programs)

BeginnerTopic: String Conversion Programs
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C++ Convert Double to Int Program

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

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

int main() {
    double num = 123.789;
    
    // Method 1: Direct casting (truncates)
    int i1 = (int)num;
    
    // Method 2: Using static_cast
    int i2 = static_cast<int>(num);
    
    // Method 3: Using floor()
    int i3 = floor(num);
    
    // Method 4: Using round()
    int i4 = round(num);
    
    cout << "Double: " << num << endl;
    cout << "Integer (cast): " << i1 << endl;
    cout << "Integer (static_cast): " << i2 << endl;
    cout << "Integer (floor): " << i3 << endl;
    cout << "Integer (round): " << i4 << endl;
    
    return 0;
}
Output
Double: 123.789
Integer (cast): 123
Integer (static_cast): 123
Integer (floor): 123
Integer (round): 124

Understanding Convert Double to Int

This program demonstrates 5 different methods to convert a double to an integer: direct casting (truncates), static_cast, floor() (rounds down), round() (rounds to nearest), and ceil() (rounds up).

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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