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例

例#include <stdio.h>double fact(int n);int main(){ int i,n; double sum; printf("Enter n"); scanf("%d",&n); sum=0; for(i=1;i<=n;i++) {sum=sum+fact(i); } printf("1!+2!+3!...+%d!=%.0f\n",n,sum); return 0;}double fact(int n