参考程序如下：#include "stdio.h"void main(){int n = 1;double fac,product = 1;do{fac = 1.0 / n / (n+1);product *= fac;n += 2;}while(product >= 1e-4);printf("n = %d\tproduct = %.6lf\n",n-2,product);}输...能给个正好的答案吗？其实这个正是正好的答案。不信，你可以看下面修改后的代码及运行结果：#include "stdio.h"void main(){int n = 1;double fac, product = 1, temp;do{temp = product;fac = 1.0 / n / (n+1);product *= fac;n += 2;}while(product >= 1e-4);printf("n = %d\tproduct = %.6lf\ttemp = %.6lf\n", n-2, product, temp);}输出结果：n = 7product = 0.000025temp = 0.001389temp是product的上一个值，只有product才满足要求，最后的temp并不满足要求。