UVa11526 H(n)
http://blog.csdn.net/synapse7/article/details/12873437
1 #include<cstdio> 2 #include<cstring> 3 #include<cstdlib> 4 #include<algorithm> 5 #include<iostream> 6 7 using namespace std; 8 9 typedef long long LL; 10 11 #include<cmath> 12 LL H(int n) { 13 LL res = 0; 14 int m = floor(sqrt(n + 0.1)); 15 for(int i = 1; i <= m; i++) { 16 res += n / i; 17 } 18 return (res << 1) - m * m; 19 } 20 21 int main() { 22 int T, n; scanf("%d", &T); 23 while(T--) { 24 scanf("%d", &n); 25 printf("%lld\n", H(n)); 26 } 27 28 return 0; 29 }
原文出处http://www.cnblogs.com/showson/