供参考:
#include<stdio.h> main() { int i,a,n; long t,s=0; printf("请输入a和n的值:"); scanf("%d%d",&a,&n); t = a;//[1] for(i=1;i<=n;i++)//[2] { s = s+t;//[3] t = t*10+a;//[4] } printf("s=%ld\n",s); //[5] }