日志6

累加

#include <iostream>

#include<cmath>

using namespace std;

int main()

{

double a,b,c,d=0,e=0,f=0;//数据要初始化

cin >> a>>b>>c;

for (int i = 1; i <= a; i++) {

d += i;

}

for (int o = 1; o <= b; o++) {

e += o*o;

}

for (double p = 1; p <= c; p++) {

f += 1/p;//p要为浮点型数据

}

printf("%.2f", d + e + f);

return 0;

}