HDU 4268 Alice and Bob(贪心+数据结构)

来源：互联网发布：珍玛奇和梁家辉知乎编辑：程序博客网时间：2024/05/16 03:03

贪心：按照宽从小到大，高从小到大，将alice和bob的卡片排序，如果宽高相同，则alice的在后面。这样所有卡片排成一排了。

每次找到alice的卡片之后，覆盖她前面的最接近她的bob的那张卡片（尽量让这张卡片最有用），然后去除掉。

#include <iostream>#include <algorithm>#include <cmath>#include <cstdio>#include <cstdlib>#include <cstring>#include <string>#include <vector>#include <set>#include <queue>#include <stack>#include <climits>//形如INT_MAX一类的#define MAX 100005#define INF 0x7FFFFFFF#define REP(i,s,t) for(int i=(s);i<=(t);++i)#define ll long long#define mem(a,b) memset(a,b,sizeof(a))#define mp(a,b) make_pair(a,b)#define L(x) x<<1#define R(x) x<<1|1# define eps 1e-5//#pragma comment(linker, "/STACK:36777216") ///传说中的外挂using namespace std;struct node {    int x,y;    int kind;} card[MAX * 2];typedef multiset<int> SET;typedef multiset<int> ::iterator IT;bool cmp(node a,node b) {    if(a.x != b.x) return a.x < b.x;    if(a.y != b.y) return a.y < b.y;    return a.kind > b.kind;}int n;int main() {    int T,i;    cin >> T;    while(T --) {        SET my;        scanf("%d",&n);        for(i=0; i<n*2; i++) {            scanf("%d%d",&card[i].x,&card[i].y);            if(i >=0 && i < n) card[i].kind = 0;            else card[i].kind = 1;        }        sort(card,card+n*2,cmp);        int ans = 0;        for(i=0; i<n*2; i++) {            if(card[i].kind == 1) my.insert(card[i].y);            else if(card[i].kind == 0 && ! my.empty() && *my.begin() <= card[i].y) {                IT it = my.upper_bound(card[i].y);                it --;                //cout << *it << ' ' << card[i].y << endl;                ans ++;                my.erase(it);            }        }        printf("%d\n",ans);    }    return 0;}