#include <stdio.h>
void main( )
{
    int i,b = 1;
    double s;
    (s = 0);/*对初始值赋值*/
    for(i = 1; i <= 15; i++)
    {
        s = s +double(i)/double(b);/*对s重新计算*/
            b=b+2;/*对b进行赋值*/
    }
    printf("%f\n", s);/*实数型输出结果*/
}