编辑代码

#include <stdio.h>

double num(double, double);

int main () {
    double num_01, num_02;
    printf("输入两个数字:");
    scanf("%lf%lf", &num_01, &num_02);
    printf("调和平均数是%.2lf", num(num_01, num_02));
	return 0;
}

double num(double num_01, double num_02)
{
    int num;
    return num = 1 / ((1 / num_01 + 1 / num_02) / 2);
}