Online C Compiler

This free online C compiler runs your program on our server with GCC 10. When your program calls scanf(), you type the input in the terminal, and you see the output, the errors and the time your program took.

It is a good fit for practice questions, college lab programs and quick tests before an exam or an interview.

1. Write your program in the editor. It must have a main() function.
2. If your program reads input with scanf(), type it in the terminal when the program asks, and press Enter. You can also put it in the Input box before you press Run.
3. Press Run. The output appears below the editor.

Open any of these from the Examples tab in the side bar.

#include <stdio.h>

int main(void) {
    printf("Hello, World!\n");
    return 0;
}

#include <stdio.h>

int main(void) {
    int a, b;
    scanf("%d %d", &a, &b);
    printf("Sum = %d\n", a + b);
    return 0;
}

#include <stdio.h>

int main(void) {
    long long result = 1;
    for (int i = 1; i <= 10; i++) {
        result *= i;
    }
    printf("10! = %lld\n", result);
    return 0;
}

C is one of the oldest programming languages that is still used every day. Operating systems, databases and small devices are written in C. Many Indian colleges teach C as the first language, because it shows how memory and the computer really work.

C is a compiled language. A compiler turns your code into a program first, and then the program runs. If the code has a mistake, the compiler stops and shows an error with a line number.

• error: expected ';' before …A semicolon is missing at the end of the line before the one shown.
• implicit declaration of function 'printf'Add #include <stdio.h> at the top of the file.
• Segmentation faultYour program used memory it does not own. Check array indexes and pointers.

• Online Python Compiler
• Online C++ Compiler
• Online Java Compiler
• Online JavaScript Compiler
• Online HTML, CSS and JavaScript Compiler
• Online SQL Compiler
• Online TypeScript Compiler
• Online React Compiler
• Online Bash Shell Compiler