7.12 编程题3

#include <stdio.h>int main(void){int n;double sumeven = 0.0;int ct_even = 0;double sumodd = 0.0;int ct_odd = 0;while (scanf("%d", &n) == 1 && n != 0){if (n % 2 == 0){sumeven += n;++ct_even;}else {sumodd += n;++ct_odd;}}printf("Number of evens: %d", ct_even);if (ct_even > 0)printf(" average: %g", sumeven / ct_even);putchar('\n');printf("Number of odds: %d", ct_odd);if (ct_odd > 0)printf(" average: %g", sumodd / ct_odd);putchar('\n');printf("\ndone\n");return 0;}