#include <stdio.h>
#include <math.h>

int main() {
    double years = 0.0;
    double percentages = 0.0;
    double sum = 0.0;
    double remain_sum;
    double sum_percents = 0.0;
    double month_sum;
    double month_percents;
    int i;
    printf("sum = ?");
    scanf("%lf", & sum);
    printf("\nyears = ?");
    scanf("%lf", & years);
    printf("\npercentages = ?");
    scanf("%lf", & percentages);
    remain_sum = sum;
    month_sum = sum / years / 12.0;
    for ( i = 0; i < (int)years * 12; i++ ) {
    	month_percents = remain_sum * percentages / 100.0 / 12.0;
    	sum_percents += month_percents;
    	remain_sum -= month_sum;
    }
    printf("\nsum_percents = %lf. Whole sum = %lf\n", sum_percents, sum + sum_percents );
    return 0;   
}