#include <stdio.h>

static unsigned triangular(unsigned n) {
    if (n == 0) { return 0; }
    return n + triangular(n - 1);
}

int main(void) {
    unsigned n = 5;
    if (n > 100) { return 1; }
    printf("Triangular total: %u\n", triangular(n));
    return 0;
}