C Loops

C has three loops: for, while (entry-controlled) and do-while (exit-controlled).

Pattern Printing with Nested for

C
#include <stdio.h>
int main() {
    for (int i = 1; i <= 4; i++) {
        for (int j = 1; j <= i; j++)
            printf("* ");
        printf("\n");
    }
    return 0;
}
* * * * * * * * * *

while: Armstrong Number

C
#include <stdio.h>
int main() {
    int n = 153, t = n, sum = 0;
    while (t > 0) {
        int d = t % 10;
        sum += d * d * d;
        t /= 10;
    }
    printf(sum == n ? "%d is Armstrong\n" : "%d is not Armstrong\n", n);
    return 0;
}
153 is Armstrong

break, continue, goto

C
for (int i = 1; i <= 10; i++) {
    if (i % 2 == 0) continue;   // skip even
    if (i > 7) break;           // stop after 7
    printf("%d ", i);
}
1 3 5 7
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