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cogs 577 . 蝗灾 cdq分治

时间:2016-07-25 14:36:33      阅读:127      评论:0      收藏:0      [点我收藏+]

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题目链接

 

两种操作, 一种将x, y这个格子+w, 另一种给出左下和右上坐标, 问你这个矩形中值的和。

 

#include <iostream>
#include <vector>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <complex>
#include <cmath>
#include <map>
#include <set>
#include <string>
#include <queue>
#include <stack>
#include <bitset>
using namespace std;
#define pb(x) push_back(x)
#define ll long long
#define mk(x, y) make_pair(x, y)
#define lson l, m, rt<<1
#define mem(a) memset(a, 0, sizeof(a))
#define rson m+1, r, rt<<1|1
#define mem1(a) memset(a, -1, sizeof(a))
#define mem2(a) memset(a, 0x3f, sizeof(a))
#define rep(i, n, a) for(int i = a; i<n; i++)
#define fi first
#define se second
typedef complex <double> cmx;
typedef pair<int, int> pll;
const double PI = acos(-1.0);
const double eps = 1e-8;
const int mod = 1e9+7;
const int inf = 1061109567;
const int dir[][2] = { {-1, 0}, {1, 0}, {0, -1}, {0, 1} };
const int maxn = 2e5+5;
struct node
{
    int x1, y1, x2, y2, w, id, sign;
    bool operator < (node a) const
    {
        return id < a.id;
    }
}a[maxn], c[maxn*2];
int sum[500005], ans[maxn], n, m;
int lowbit(int x)
{
    return x & (-x);
}
void update(int x, int val)
{
    while(x <= m) {
        sum[x] += val;
        x += lowbit(x);
    }
}
int query(int x)
{
    int ret = 0;
    while(x) {
        ret += sum[x];
        x -= lowbit(x);
    }
    return ret;
}
bool cmp(const node& a, const node& b)
{
    if(a.x1 != b.x1)
        return a.x1 < b.x1;
    return a.sign < b.sign;
}
void cdq(int l, int r)
{
    if(l == r)
        return ;
    int m = l+r>>1;
    cdq(l, m);
    cdq(m+1, r);
    int num = 0;
    for(int i = l; i <= m; i++) {
        if(a[i].sign == 1) {
            c[num++] = a[i];
        }
    }
    for(int i = m + 1; i <= r; i++) {
        if(a[i].sign == 2) {
            c[num++] = a[i];
            c[num-1].x1--;
            c[num++] = a[i];
            c[num-1].x1 = c[num-1].x2;
            c[num-1].sign = 3;
        }
    }
    sort(c, c+num, cmp);
    for(int i = 0; i < num; i++) {
        if(c[i].sign == 1) {
            update(c[i].y1, c[i].w);
        } else if(c[i].sign == 2) {
            ans[c[i].id] -= (query(c[i].y2) - query(c[i].y1 - 1));
        } else {
            ans[c[i].id] += (query(c[i].y2) - query(c[i].y1 - 1));
        }
    }
    for(int i = l; i <= m; i++) {
        if(a[i].sign == 1) {
            update(a[i].y1, -a[i].w);
        }
    }
}
int main()
{
    freopen ( "locust.in" , "r" , stdin ) ;
    freopen ( "locust.out" , "w" , stdout ) ;
    while(cin>>m>>n) {
        for(int i = 1; i <= n; i++) {
            scanf("%d", &a[i].sign);
            if(a[i].sign == 1) {
                scanf("%d%d%d", &a[i].x1, &a[i].y1, &a[i].w);
            } else {
                scanf("%d%d%d%d", &a[i].x1, &a[i].y1, &a[i].x2, &a[i].y2);
            }
            a[i].id = i;
        }
        mem(sum);
        mem(ans);
        cdq(1, n);
        for(int i = 1; i <= n; i++) {
            if(a[i].sign == 2) {
                printf("%d\n", ans[i]);
            }
        }
    }
    return 0;
}

 

cogs 577 . 蝗灾 cdq分治

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原文地址:http://www.cnblogs.com/yohaha/p/5703150.html

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