UVaLive 6602 Counting Lattice Squares (找规律)

题意：给定一个n*m的矩阵，问你里面有几面积为奇数的正方形。

析：首先能知道的是，大的矩阵是包括小的矩阵的，而且面积为奇数，我们只要考虑恰好在边界上的正方形即可，画几个看看就知道了，如果是3*3的有3个，

5*5有5个，偶数没有，因为面积为奇数。那么结果就有了。

代码如下：

#pragma comment(linker, "/STACK:1024000000,1024000000")
#include <cstdio>
#include <string>
#include <cstdlib>
#include <cmath>
#include <iostream>
#include <cstring>
#include <set>
#include <queue>
#include <algorithm>
#include <vector>
#include <map>
#include <cctype>
#include <cmath>
#include <stack>
#include <sstream>
#define frer freopen("in.txt", "r", stdin)
#define frew freopen("out.txt", "w", stdout)
using namespace std;

typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int, int> P;
const int INF = 0x3f3f3f3f;
const double inf = 0x3f3f3f3f3f3f;
const double PI = acos(-1.0);
const double eps = 1e-8;
const int maxn = 5e5 + 5;
const int mod = 1e9 + 7;
const char *mark = "+-*";
const int dr[] = {1, 0, -1, 0};
const int dc[] = {0, 1, 0, -1};
const char *de[] = {"0000", "0001", "0010", "0011", "0100", "0101", "0110", "0111", "1000", "1001", "1010", "1011", "1100", "1101", "1110", "1111"};
int n, m;
const int mon[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int monn[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
inline int Min(int a, int b){ return a < b ? a : b; }
inline int Max(int a, int b){ return a > b ? a : b; }
inline LL Min(LL a, LL b){ return a < b ? a : b; }
inline LL Max(LL a, LL b){ return a > b ? a : b; }
inline bool is_in(int r, int c){
    return r >= 0 && r < n && c >= 0 && c < m;
}

int main(){
    while(scanf("%d %d", &n, &m) && n){
        LL ans = 0;
        int t = Min(n, m);
        for(int i = 3; i <= t; i += 2)
            ans += (LL)i * (LL)(n+1-i) * (LL)(m+1-i);
        ans += (LL)n * (LL)m;
        cout << ans << endl;
    }
    return 0;
}