Example: Fibonacci Series - Iterative Method in C

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// Fibonacci Series - Iterative Method
#include <stdio.h>

int main() {
    // Step 1: Declare variables for the first two terms, the next term, and the number of terms.
    int t1 = 0, t2 = 1, nextTerm;
    int n, i;

    // Step 2: Prompt the user to enter the number of terms.
    printf("Enter the number of terms: ");
    scanf("%d", &n);

    // Step 3: Print a message indicating the series.
    printf("Fibonacci Series: ");

    // Step 4: Loop to generate and print the series.
    for (i = 1; i <= n; ++i) {
        // Step 4.1: Print the first term if it's the first iteration, otherwise print the current t1.
        printf("%d, ", t1);

        // Step 4.2: Calculate the next term.
        nextTerm = t1 + t2;

        // Step 4.3: Update t1 and t2 for the next iteration.
        t1 = t2;
        t2 = nextTerm;
    }
    printf("\n"); // Newline for better formatting
    return 0;
}