Sum of Numbers from 1 to n in C

April 04, 2026

C Pattern Programs: Square Number and Alphabet Patterns Explained

🔷 Square Star Pattern 📋 Copy Code #include <stdio.h> int main() { int num; printf("Enter the number:\n"); scanf("%d", &num); for(int i = 1; i <= num; i++) { for(int j = 1; j <= num; j++) { printf("* ");//keep"* " } printf("\n"); } return 0; } 🔷 Reverse Square Alphabet Pattern (Column-wise) 📋 Copy Code #include <stdio.h> int main() { int num; printf("Enter the number:\n"); scanf("%d", &num); for(int i = num; i >= 1; i--) { for(int j = num; j >= 1; j--) { printf("%c ", j + 64);//%c for Character and 64 will be ASIIC VALUE } printf("\n"); } return 0; } 🔷 Reverse Square Alphabet Pattern (Row-wise) 📋 Copy Code #include <stdio.h> int main() { int num; ...

✅ C Program to Calculate Sum from 1 to n

#include <stdio.h>

int main() {
    int n, sum = 0;

    printf("Enter a positive number: ");
    scanf("%d", &n);

    if (n <= 0) {
        printf("Please enter a positive number.\n");
        return 1;
    }

    for (int i = 1; i <= n; i++) {
        sum += i;
    }

    printf("Sum of numbers from 1 to %d is: %d\n", n, sum);

    return 0;
}

📘 Explanation:

✅ This program calculates the sum of all natural numbers from 1 to n.
✅ It uses a for loop to iterate from 1 to the given number n.
✅ On each iteration, it adds the value to a running sum variable.
✅ If the input is non-positive, it displays an error message.

🧾 Sample Output:

Enter a positive number: 5
Sum of numbers from 1 to 5 is: 15

🔑 Keywords:

Sum from 1 to n in C, C loop program, C addition logic, beginner C project, for loop in C, positive number sum

📌 Hashtags:

#CProgramming #ForLoop #BeginnerC #MathInC #SumOfNumbers #InterviewPrep #CodingBasics

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C Pattern Programs: Square Number and Alphabet Patterns Explained