poj3497

二分+排序

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <cstdio>
#include <algorithm>
using namespace std;

#define maxn 1005
#define maxl 25

struct Elem
{
    int id, quality, price;
}elem[maxn];

int n, budget;
char name[maxn][maxl];
int tot;
bool vis[maxn];
int f[maxn];

bool operator < (const Elem &a, const Elem &b)
{
    return a.price < b.price;
}

int getid(char *st)
{
    for (int i = 0; i < tot; i++)
        if (strcmp(st, name[i]) == 0)
            return i;
    strcpy(name[tot], st);
    return tot++;
}

void input()
{
    char st[maxl];
    scanf("%d%d", &n, &budget);
    tot = 0;
    for (int i = 0; i < n; i++)
    {
        scanf("%s", st);
        elem[i].id = getid(st);
        scanf("%s%d%d", st, &elem[i].price, &elem[i].quality);
    }
}

bool ok(int a)
{
    int cnt = 0;
    long long temp = 0;
    memset(vis, 0, sizeof(vis));
    for (int i = 0; i < n; i++)
        if (!vis[elem[i].id] && elem[i].quality >= a)
        {
            vis[elem[i].id] = true;
            cnt++;
            temp += elem[i].price;
        }
    return temp <= budget;
}

int binarysearch()
{
    int l = 0;
    int r = 1000000000;
    memset(f, 0, sizeof(f));
    for (int i = 0; i < n; i++)
        f[elem[i].id] = max(f[elem[i].id], elem[i].quality);
    for (int i = 0; i < tot; i++)
        r = min(r, f[i]);
    while (l < r)
    {
        int mid = (l + r + 1) / 2;
        if (!ok(mid))
            r = mid - 1;
        else
            l = mid;
    }
    return l;
}

int main()
{
    //freopen("t.txt", "r", stdin);
    int t;
    scanf("%d", &t);
    while (t--)
    {
        input();
        sort(elem, elem + n);
        int ans = binarysearch();
        printf("%d\n", ans);
    }
    return 0;
}