Create arrays A, B and C of size 3, perform C = A + B.

Learn how to perform element-wise addition of two arrays in C

array_addition.c

#include <stdio.h>

int main() {
    int A[3], B[3], C[3];
    int i;

    // Input elements of array A
    printf("Enter 3 elements of array A:\n");
    for(i = 0; i < 3; i++) {
        printf("A[%d]: ", i);
        scanf("%d", &A[i]);
    }

    // Input elements of array B
    printf("\nEnter 3 elements of array B:\n");
    for(i = 0; i < 3; i++) {
        printf("B[%d]: ", i);
        scanf("%d", &B[i]);
    }

    // Add elements of A and B, store in C
    for(i = 0; i < 3; i++) {
        C[i] = A[i] + B[i];
    }

    // Display result
    printf("\nResultant array C (A + B):\n");
    for(i = 0; i < 3; i++) {
        printf("C[%d] = %d\n", i, C[i]);
    }

    return 0;
}

🧾 Step-by-Step Explanation

🔹 Step 1: Include Header File

#include <stdio.h>

This includes the standard input-output library which provides:

• printf() for output display
• scanf() for user input
• Other essential I/O functions

🔹 Step 2: Declare Arrays and Variables

int A[3], B[3], C[3];
int i;

• A[3] and B[3]: Arrays to store user inputs (3 elements each)
• C[3]: Array to store the sum of corresponding elements
• i: Loop counter variable for array traversal

🔹 Step 3: Input Values in Array A

for(i = 0; i < 3; i++) {
    printf("A[%d]: ", i);
    scanf("%d", &A[i]);
}

This loop:

• Runs 3 times (i = 0 to 2)
• Prompts user for each element with index position
• Stores input values in array A
• Uses &A[i] to get memory address for storage

🔹 Step 4: Input Values in Array B

for(i = 0; i < 3; i++) {
    printf("B[%d]: ", i);
    scanf("%d", &B[i]);
}

Similar to Step 3, but for array B:

• Same loop structure
• Stores values in array B
• Maintains parallel indexing with array A

🔹 Step 5: Add Corresponding Elements

for(i = 0; i < 3; i++) {
    C[i] = A[i] + B[i];
}

Performs element-wise addition:

• Adds A[0] + B[0] and stores in C[0]
• Adds A[1] + B[1] and stores in C[1]
• Adds A[2] + B[2] and stores in C[2]
• Process is called vector addition

🔹 Step 6: Display Result

for(i = 0; i < 3; i++) {
    printf("C[%d] = %d\n", i, C[i]);
}

Outputs the result array C:

• Prints each element with its index
• Uses \n for newline between elements
• Shows the sum of corresponding elements from A and B

🧪 Sample Output

Enter 3 elements of array A:
A[0]: 2
A[1]: 4
A[2]: 6

Enter 3 elements of array B:
B[0]: 1
B[1]: 3
B[2]: 5

Resultant array C (A + B):
C[0] = 3
C[1] = 7
C[2] = 11

📌 Key Concepts Covered

Array

A linear data structure that stores elements of the same type in contiguous memory

Element-wise Addition

Adding corresponding elements from two arrays of the same size

for Loop

Control structure used to traverse and process array elements sequentially

Array Indexing

Accessing individual array elements using their position (0-based index)

I/O Operations

Using printf() and scanf() for formatted output and input