#include<stdio.h>int main(void){ int i,b=1; double s; s=0; /*s赋值*/ for(i=1;i<=15;i++) { s=s+double(i)/double(b);/*将整型强制变换成浮点型*/ b=b+2; /*进行循环*/ } printf("sum = %f " ,s);/*sum以浮点型输出*/}