HDU 6514 Monitor (二维前缀和 差分)

二维前缀和 差分

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=6514

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <map>
#include <set>
#include <vector>
#include <string>
#include <cmath>
#include <queue>
#define rep(i, s, e) for(int i = s; i < e; ++i)
#define P pair<int, int>
#define INF 0x3f3f3f3f
using namespace std;
typedef long long ll;
static const int N = 2020;
static const int MAX_N = 1e4 + 5;
static const ll Mod = 1e9 + 7;
void add(int n, int m, vector<vector<int> >&vec){
    for(int i = 1; i <= n; ++i){
        for(int j = 1; j <= m; ++j){
            vec[i][j] += vec[i - 1][j] + vec[i][j - 1] - vec[i - 1][j - 1];
        }
    }
}
void solve(){
//    freopen("input.txt", "r", stdin);
//    freopen("output.txt", "w", stdout);
    //ios::sync_with_stdio(false);
    int n, m;
    while(scanf("%d%d", &n, &m) != EOF){
        vector<vector<int> >vec(n + 5, vector<int>(m + 5));
        int p;
        scanf("%d", &p);
        while(p--){
            int x1, x2, y1, y2;
            scanf("%d%d%d%d", &x1, &y1, &x2, &y2);
            vec[x1][y1]++;
            vec[x1][y2 + 1]--;
            vec[x2 + 1][y1]--;
            vec[x2 + 1][y2 + 1]++;
        }
        add(n, m, vec);
        for(int i = 1; i <= n; ++i){
            for(int j = 1; j <= m; ++j){
                if(vec[i][j]) vec[i][j] = 1;
            }
        }
        add(n, m, vec);
        int q;
        scanf("%d", &q);
        while(q--){
            int x1, x2, y1, y2;
            scanf("%d%d%d%d", &x1, &y1, &x2, &y2);
            int rec = vec[x2][y2] - vec[x1 - 1][y2] - vec[x2][y1 - 1] + vec[x1 - 1][y1 - 1];
            if(rec == (x2 - x1 + 1) * (y2 - y1 + 1)) puts("YES");
            else puts("NO");
        }
    }
}
int main() {
    solve();
    return 0;
}

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