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POJ2584_T-Shirt Gumbo(二分图多重最大匹配/最大流)

解题报告

http://blog.csdn.net/juncoder/article/details/38239367

题目传送门

题意:

X个参赛选手,每个选手有衣服大小的范围,5种大小的队服,求是否能使每个选手都拿到符合自己大小范围的衣服。

思路:

X人5种衣服,有的人选的衣服可能大小一样,这样就是二分图的多重最大匹配。源点到5种衣服的容量就是衣服的数量。

#include <queue>
#include <queue>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#define inf 99999999
using namespace std;
int n,mmap[30][30],m,l[30],t;
int T_shirt[30];
int bfs()
{
    queue<int >Q;
    Q.push(0);
    memset(l,-1,sizeof(l));
    l[0]=0;
    while(!Q.empty()) {
        int u=Q.front();
        Q.pop();
        for(int i=0; i<=m; i++) {
            if(l[i]==-1&&mmap[u][i]) {
                l[i]=l[u]+1;
                Q.push(i);
            }
        }
    }
    if(l[m]>1)return 1;
    else return 0;
}
int dfs(int x,int f)
{
    int a;
    if(x==m)return f;
    for(int i=0; i<=m; i++) {
        if(mmap[x][i]&&l[i]==l[x]+1&&(a=dfs(i,min(f,mmap[x][i])))) {
            mmap[x][i]-=a;
            mmap[i][x]+=a;
            return a;
        }
    }
    l[x]=-1;
    return 0;
}
int main()
{
    int i,j;
    char str[100];
    char s[10];
    T_shirt['S'-'A']=1;
    T_shirt['M'-'A']=2;
    T_shirt['L'-'A']=3;
    T_shirt['X'-'A']=4;
    T_shirt['T'-'A']=5;
    while(cin>>str) {
        memset(mmap,0,sizeof(mmap));
        if(!strcmp(str,"ENDOFINPUT"))
            break;
        if(!strcmp(str,"END"))
            continue;
        cin>>n;
        m=n+5+1;
        for(i=1; i<=n; i++) {
            cin>>s;
            int a=T_shirt[s[0]-'A'];
            int b=T_shirt[s[1]-'A'];
            if(a>b)
                swap(a,b);
            for(j=a; j<=b; j++) {
                mmap[j][i+5]=1;
            }
            mmap[i+5][m]=1;
        }
        for(i=1; i<=5; i++) {
            scanf("%d",&t);
            mmap[0][i]=t;
        }
        int ans=0;
        cin>>str;
        while(bfs())
            while(t=dfs(0,inf))
                ans+=t;
        if(ans==n)
            cout<<"T-shirts rock!"<<endl;
        else cout<<"I'd rather not wear a shirt anyway..."<<endl;
        if(!strcmp(str,"END"))continue;
    }
    return 0;
}

T-Shirt Gumbo
Time Limit: 1000MS Memory Limit: 65536K
Total Submissions: 2621 Accepted: 1223

Description

Boudreaux and Thibodeaux are student volunteers for this year‘s ACM South Central Region‘s programming contest. One of their duties is to distribute the contest T-shirts to arriving teams. The T-shirts had to be ordered in advance using an educated guess as to how many shirts of each size should be needed. Now it falls to Boudreaux and Thibodeaux to determine if they can hand out T-shirts to all the contestants in a way that makes everyone happy.

Input

Input to this problem will consist of a (non-empty) series of up to 100 data sets. Each data set will be formatted according to the following description, and there will be no blank lines separating data sets. 

A single data set has 4 components: 
  1. Start line - A single line: 
    START X 

    where (1 <= X <= 20) is the number of contestants demanding shirts. 
  2. Tolerance line - A single line containing X space-separated pairs of letters indicating the size tolerances of each contestant. Valid size letters are S - small, M - medium, L - large, X - extra large, T - extra extra large. Each letter pair will indicate the range of sizes that will satisfy a particular contestant. The pair will begin with the smallest size the contestant will accept and end with the largest. For example: 
    MX 

    would indicate a contestant that would accept a medium, large, or extra large T-shirt. If a contestant is very picky, both letters in the pair may be the same. 
  3. Inventory line - A single line: 
    S M L X T 

    indicating the number of each size shirt in Boudreaux and Thibodeaux‘s inventory. These values will be between 0 and 20 inclusive. 
  4. End line - A single line: 
    END 

After the last data set, there will be a single line: 
ENDOFINPUT 

Output

For each data set, there will be exactly one line of output. This line will reflect the attitude of the contestants after the T-shirts are distributed. If all the contestants were satisfied, output: 

T-shirts rock! 

Otherwise, output: 
I‘d rather not wear a shirt anyway... 

Sample Input

START 1
ST
0 0 1 0 0
END
START 2
SS TT
0 0 1 0 0
END
START 4
SM ML LX XT
0 1 1 1 0
END
ENDOFINPUT

Sample Output

T-shirts rock!
I‘d rather not wear a shirt anyway...
I‘d rather not wear a shirt anyway...

Source

South Central USA 2003