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[][] = { {,}, {-,}, {,}, {,-}, {,}, {,-}, {-,}, {-,-} };

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=; i<=n; i++)

            scanf("%d", &h[i]);

        for(int i=n; i>=; i--)

                mp[h[i]].push_back(i);

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

            if(mp[q[i]].size()>=)
            {
                printf("%d\n", mp[q[i]].back());

                mp[q[i]].pop_back();
            }
            else

                printf("-1\n");
        }
    }
    return ;
}

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[][] = { {,}, {-,}, {,}, {,-}, {,}, {,-}, {-,}, {-,-} };

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 = -;

    while(L <= R)
    {
        int Mid = (L+R)/;

        if(num == h[Mid].num)
        {
            if(!vis[Mid])
            {
                ans = Mid;

                R = Mid - ;///先输出最左边的；
            }
            else
                L = Mid + ;
        }
        else if(h[Mid].num > num)

            R = Mid - ;
        else

            L = Mid + ;
    }
    if(ans != -)
    {
        vis[ans] = ;
        return h[ans].Id;
    }
    return -;
}

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

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

            h[i].Id = i+;
        }

        sort(h, h+n, cmp);

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

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

            printf("%d\n", pos);
        }
    }
    return ;
}