问答题

编写方法double sumS(int n)，已知参数n，求以下表达式前n项的和S返回。


注：下一项的分母=上一项的分子，下一项的分子=上一项的分子与分母的和。

【参考答案】

double sumS(int n){
double S,fz,fm,temp;
S=0.0;fz=......

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