Easy C Code Snippets
Explore these C code examples that you can easily copy and use in your own projects.
Basic Hello World
// Include stdio.h #include int main() { printf("Hello, World!\n"); return 0; }
Simple For Loop
// Include stdio.h #include int main() { for (int i = 0; i < 5; i++) { printf("%d\n", i); } return 0; }
Basic Calculator
// Include stdio.h #include int main() { char operator; double first, second; printf("Enter an operator (+, -, *, /): "); scanf("%c", &operator); printf("Enter two operands: "); scanf("%lf %lf", &first, &second); switch (operator) { case '+': printf("%.1lf + %.1lf = %.1lf", first, second, first + second); break; case '-': printf("%.1lf - %.1lf = %.1lf", first, second, first - second); break; case '*': printf("%.1lf * %.1lf = %.1lf", first, second, first * second); break; case '/': printf("%.1lf / %.1lf = %.1lf", first, second, first / second); break; default: printf("Operator is not correct"); } return 0; }
Temperature Converter
// Include stdio.h #include double celsiusToFahrenheit(double celsius) { return (celsius * 9 / 5) + 32; } double fahrenheitToCelsius(double fahrenheit) { return (fahrenheit - 32) * 5 / 9; } int main() { double temperature; char unit; printf("Enter temperature with unit (C or F): "); scanf("%lf %c", &temperature, &unit); if (unit == 'C' || unit == 'c') { printf("%.2lf C = %.2lf F", temperature, celsiusToFahrenheit(temperature)); } else if (unit == 'F' || unit == 'f') { printf("%.2lf F = %.2lf C", temperature, fahrenheitToCelsius(temperature)); } else { printf("Invalid unit"); } return 0; }
Guess the Number Game
// Include stdio.h, stdlib.h and time.h #include int main() { int number, guess, attempts = 0; srand(time(0)); number = rand() % 100 + 1; // Random number between 1 and 100 printf("Guess the number (1 to 100): "); do { scanf("%d", &guess); attempts++; if (guess > number) { printf("Lower!\n"); } else if (guess < number) { printf("Higher!\n"); } else { printf("You guessed it in %d attempts!", attempts); } } while (guess != number); return 0; }
Simple ATM Interface
// Include stdio.h #include int main() { int choice; float balance = 1000.00; float amount; while (1) { printf("ATM Menu:\n"); printf("1. Check Balance\n"); printf("2. Withdraw Money\n"); printf("3. Deposit Money\n"); printf("4. Exit\n"); printf("Choose an option: "); scanf("%d", &choice); switch (choice) { case 1: printf("Balance: $%.2f\n", balance); break; case 2: printf("Enter amount to withdraw: "); scanf("%f", &amount); if (amount > balance) { printf("Insufficient balance\n"); } else { balance -= amount; printf("New balance: $%.2f\n", balance); } break; case 3: printf("Enter amount to deposit: "); scanf("%f", &amount); balance += amount; printf("New balance: $%.2f\n", balance); break; case 4: printf("Exiting...\n"); return 0; default: printf("Invalid option\n"); } } return 0; }
Palindrome Checker
// Include stdio.h, string.h and stdbool.h #include bool isPalindrome(char str[]) { int l = 0; int h = strlen(str) - 1; while (h > l) { if (str[l++] != str[h--]) { return false; } } return true; } int main() { char str[100]; printf("Enter a string: "); scanf("%s", str); if (isPalindrome(str)) printf("%s is a palindrome.", str); else printf("%s is not a palindrome.", str); return 0; }
Simple Interest Calculator
// Include stdio.h #include int main() { double principal, rate, time, interest; printf("Enter principal amount: "); scanf("%lf", &principal); printf("Enter rate of interest: "); scanf("%lf", &rate); printf("Enter time period (in years): "); scanf("%lf", &time); interest = (principal * rate * time) / 100.0; printf("Simple Interest = %.2lf\n", interest); return 0; }
Factorial Calculator
// Include stdio.h #include unsigned long long factorial(int n) { if (n == 0 || n == 1) { return 1; } else { return n * factorial(n - 1); } } int main() { int num; printf("Enter a positive integer: "); scanf("%d", &num); if (num < 0) { printf("Factorial is not defined for negative numbers.\n"); } else { unsigned long long fact = factorial(num); printf("Factorial of %d = %llu\n", num, fact); } return 0; }
Fibonacci Series Generator
// Include stdio.h #include void generateFibonacci(int n) { int a = 0, b = 1, next; printf("Fibonacci Series (first %d terms): ", n); for (int i = 1; i <= n; i++) { if (i == 1) printf("%d, ", a); else if (i == 2) printf("%d, ", b); else { next = a + b; printf("%d, ", next); a = b; b = next; } } printf("\n"); } int main() { int terms; printf("Enter the number of terms for the Fibonacci series: "); scanf("%d", &terms); generateFibonacci(terms); return 0; }
Prime Number Checker
// Include stdio.h and stdbool.h #include bool isPrime(int num) { if (num <= 1) return false; for (int i = 2; i * i <= num; i++) { if (num % i == 0) return false; } return true; } int main() { int num; printf("Enter a positive integer: "); scanf("%d", &num); if (isPrime(num)) { printf("%d is a prime number.\n", num); } else { printf("%d is not a prime number.\n", num); } return 0; }