# include & ltstdio.h & gt
雙倍?fenshi(int?x){
雙倍?q,尚=1.0,夏= 1.0;
int?我;
for(I = 1;我& lt= x;i++){
尚* = I;
夏* = 2 * I+1;
}
q =商/夏;
回歸?q;
}
int?main(){
雙倍?eps,sum = 0.00000//sum初始化為0。
int?j;
scanf("%le ",& ampEPS);
如果(eps & lt=0) {
printf("PI?=?0");
回歸?0;
}
for(j = 0;;j++){//基於j 0的枚舉
sum+= fenshi(j);
if(fenshi(j)& lt;eps)破;
}
printf("PI?=?%.5f”,2 * sum);
回歸?0;
}