C语言：输入x和n,计算并输出式子的值,S=x/1+x/3+…x/n

输入x和n,计算并输出式子的值,S=x/1+x/3+…x/n

```c
#include<stdio.h>
int main()
{
    int x = 0;
    int n = 0;
    scanf("%d %d", &x, &n);
    //由于除法得到的结果有的是小数，所以用double类型变量
    double sum = 0;//用来求和
    double i = 0;
    //分母从1开始，每次加2，直到n，1 3 5 7 9 ... n
    for (i = 1.0; i <= n; i += 2.0)
    {
        sum += x / i;//每次的结果加起来
    }
    //以小数形式打印，如果保存两位小数，就写成%.2lf
    printf("%lf", sum);
    return 0;
}

```

供参考：

#include <stdio.h>
int main()
{
    int n, i;
    double s = 0, x;
    scanf("%lf %d", &x, &n);
    for (i = 1; i <= n; i+=2)
        s += x * 1.0 / i;
    printf("S=%f", s);
    return 0;
}

#include <stdio.h>
int main()
{
    int n;
    double sum=0, x;
    scanf("%lf%d", &x, &n);
    for (int i = 1; i <= n; i+=2)
        sum += x / i;
    printf("%lf", sum);
}