题目1082：代理服务器(贪心算法)

//
//  1082 代理服务器.cpp
//  Jobdu
//
//  Created by PengFei_Zheng on 03/05/2017.
//  Copyright © 2017 PengFei_Zheng. All rights reserved.
//

#include <stdio.h>
#include <iostream>
#include <algorithm>
#include <string.h>
#include <cstring>
#include <cmath>
#include <climits>
#define MAX_SIZE 1001
#define MAX_SERVER 5001
//#define debug
using namespace std;

int n, m;

struct Server{//define the struct of server
int x, y, z, w;
bool operator == (const Server &a) const{//reload the == operator
return (x==a.x && y==a.y && z==a.z && w==a.w);
}
};

Server s1[MAX_SIZE];
Server s2[MAX_SERVER];

int main(){
#ifdef debug
freopen("/Users/pengfei_zheng/Desktop/input.txt", "r", stdin);
#endif
while(scanf("%d",&n)!=EOF){
for(int i = 0 ; i < n ; i++){
scanf("%d.%d.%d.%d",&s1[i].x,&s1[i].y,&s1[i].z,&s1[i].w);
}
scanf("%d",&m);
for(int i = 0 ; i < m ; i++){
scanf("%d.%d.%d.%d",&s2[i].x,&s2[i].y,&s2[i].z,&s2[i].w);
}
if(1==n){//special case
int i;
for(i = 0 ; i < m ; i++){
if(s1[0]==s2[i]){
break;
}
}
if(i<m) printf("-1\n");
else printf("0\n");
}
else{
bool loopFlag = true;
int start=0, ans = 0, idx = 0;
int maxIdx;
while(loopFlag){
maxIdx = -1;
loopFlag = false;
for(int i = 0 ; i < n ; i++){
idx = start;
while(idx < m && !(s1[i]==s2[idx])){
idx++;
}
maxIdx = max(maxIdx,idx);// find the last appear server
}
if(maxIdx < m){ //judge whether this server can reach all the other servers
ans++;
loopFlag = true;
}
start =  maxIdx + 1; //update the start Idx
}
printf("%d\n",ans);
}
}
return 0;
}
/**************************************************************
Problem: 1082
User: zpfbuaa
Language: C++
Result: Accepted
Time:10 ms
Memory:1612 kb
****************************************************************/