编写C语言程序求sum=1+1/12+1/123+1/1234+1/12345的值，急需

include int main() { int i,j,n,sum; double num=0.; scanf("%d",&n); for(i=1;i<=n;i++) { sum=0; for(j=1;j<=i;j++) sum=sum*10+j; num+=1.0/sum; } printf(&qu