hdu2063过山车
1、匈牙利算法;
2、二分图最大匹配
import java.util.Scanner; public class Main { public static boolean find(int cur, int[] pre, boolean[][] map, boolean[] vis){ for (int i = 1; i < pre.length; i++) { if (map[cur][i] && !vis[i]){ vis[i] = true; if (pre[i]==-1 || find(pre[i],pre,map,vis)){ pre[i] = cur; return true; } } } return false; } public static void main(String[] args) { Scanner sc = new Scanner(System.in); while (sc.hasNext()){ int hang = sc.nextInt(); if (hang==0){ break; } int res = 0; int girl = sc.nextInt(); int boy = sc.nextInt(); /*女找男*/ int[] pre = new int[boy+1];/*记录男的被谁选择了*/ boolean[][] map = new boolean[girl+1][boy+1]; boolean[] vis = new boolean[boy+1];/*临时记录男的是否 被选*/ for (int i = 1; i <= boy; i++) { pre[i] = -1; } for (int i = 0; i < hang; i++) { int aa = sc.nextInt(); int bb = sc.nextInt(); map[aa][bb] = true; } for (int i = 1; i <=girl ; i++) { for (int j = 1; j <=boy ; j++) { vis[j] = false; } if (find(i,pre,map,vis)){ res++; } } System.out.println(res); } } }