Gunner II--hdu5233（map&vector/二分）

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=5233

题意：有n颗树，第 i 棵树的高度为 h[i]，树上有鸟，现在这个人要打m次枪，每次打的高度是 q[i], 求每次

打枪能打下鸟的编号，否则输出-1 ；

STL中的map和vector：

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <algorithm>
#include <map>

using namespace std;

#define met(a, b) memset(a, b, sizeof(a))
#define INF 0x3f3f3f3f
#define N 100010

int dir[8][2] = { {1,0}, {-1,0}, {0,1}, {0,-1}, {1,1}, {1,-1}, {-1,1}, {-1,-1} };


int n, m, h[N], q[N];

map<int, vector<int> > mp;

int main()
{
    while(scanf("%d %d", &n, &m) != EOF)
    {
        mp.clear();
        
        for(int i=1; i<=n; i++)

            scanf("%d", &h[i]);
    
        for(int i=n; i>=1; i--)
            
                mp[h[i]].push_back(i);
            
        for(int i=1; i<=m; i++)
        {
            scanf("%d", &q[i]);
            
            if(mp[q[i]].size()>=1)
            {
                printf("%d
", mp[q[i]].back());
                
                mp[q[i]].pop_back();
            }
            else
            
                printf("-1
");
        }
    }
    return 0;
}

二分：

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <algorithm>
#include <map>

using namespace std;

#define met(a, b) memset(a, b, sizeof(a))
#define INF 0x3f3f3f3f
#define N 100010

int dir[8][2] = { {1,0}, {-1,0}, {0,1}, {0,-1}, {1,1}, {1,-1}, {-1,1}, {-1,-1} };

struct node
{
    int num, Id;
}h[N];

int n, m, q[N], vis[N];

int cmp(node a, node b)
{
    if(a.num!=b.num)
        return a.num < b.num;
    return a.Id < b.Id;
}

int BeSearch(int L, int R, int num)
{
    int ans = -1;
    
    while(L <= R)
    {
        int Mid = (L+R)/2;
        
        if(num == h[Mid].num)
        {
            if(!vis[Mid])
            {
                ans = Mid;
                
                R = Mid - 1;///先输出最左边的；
            }
            else
                L = Mid + 1;
        }
        else if(h[Mid].num > num)
            
            R = Mid - 1;
        else
            
            L = Mid + 1;
    }
    if(ans != -1)
    {
        vis[ans] = 1;
        return h[ans].Id;
    }
    return -1;
}

int main()
{
    while(scanf("%d %d", &n, &m) != EOF)
    {
        met(vis, 0);
        met(h, 0);
        met(q, 0);

        for(int i=0; i<n; i++)
        {
            scanf("%d", &h[i].num);
           
            h[i].Id = i+1;
        }

        sort(h, h+n, cmp);

        for(int i=1; i<=m; i++)
        {
            scanf("%d", &q[i]);

            int pos = BeSearch(0, n, q[i]);

            printf("%d
", pos);
        }
    }
    return 0;
}