HDU-2114 Calculate S(n)
Description
Calculate S(n).
S(n)=13+23 +33 +......+n3 .
Input
Each line will contain one integer N(1 < n < 1000000000). Process to end of file.
Output
For each case, output the last four dights of S(N) in one line.
Sample Input
1
2
Sample Output
0001
0009
生搬硬套公式。
#include <iostream> #include <cstdio> using namespace std; int main(void) { long long t; while(cin >> t) { long long sum; sum = ((t*(t+1)/2) % 10000) * ((t*(t+1)/2) % 10000) % 10000; printf("%04lld\n", sum); } return 0; }
1到n的立方和的公式——1³+2³+3³+.+n³=[n(n+1)]²/4
立方和公式——
立方差公式——
int 的取值范围 -2147483648~2147483647(-2^31~2^31-1)
long、long long 的取值范围 -9223372036854775808~9223372036854775807(-2^63~2^63-1)