1148 Werewolf - Simple Version (20 point(s))

1148 Werewolf - Simple Version (20 point(s))

Werewolf（狼人杀） is a game in which the players are partitioned into two parties: the werewolves and the human beings. Suppose that in a game,

• player #1 said: "Player #2 is a werewolf.";
• player #2 said: "Player #3 is a human.";
• player #3 said: "Player #4 is a werewolf.";
• player #4 said: "Player #5 is a human."; and
• player #5 said: "Player #4 is a human.".

Given that there were 2 werewolves among them, at least one but not all the werewolves were lying, and there were exactly 2 liars. Can you point out the werewolves?

Now you are asked to solve a harder version of this problem: given that there were N players, with 2 werewolves among them, at least one but not all the werewolves were lying, and there were exactly 2 liars. You are supposed to point out the werewolves.

Input Specification:

Each input file contains one test case. For each case, the first line gives a positive integer N (5≤N≤100). Then N lines follow and the i-th line gives the statement of the i-th player (1≤i≤N), which is represented by the index of the player with a positive sign for a human and a negative sign for a werewolf.

Output Specification:

If a solution exists, print in a line in ascending order the indices of the two werewolves. The numbers must be separated by exactly one space with no extra spaces at the beginning or the end of the line. If there are more than one solution, you must output the smallest solution sequence -- that is, for two sequences A=a[1],...,a[M] and B=b[1],...,b[M], if there exists 0≤k<M such that a[i]=b[i] (i≤k) and a[k+1]<b[k+1], then A is said to be smaller than B. In case there is no solution, simply print No Solution.

Sample Input 1:

5
-2
+3
-4
+5
+4

Sample Output 1:

1 4

Sample Input 2:

6
+6
+3
+1
-5
-2
+4

Sample Output 2 (the solution is not unique):

1 5

Sample Input 3:

5
-2
-3
-4
-5
-1

Sample Output 3:

No Solution

简单模拟。狼人杀的N个参赛者中有一名平民和一名狼人说谎，根据他们的描述，找出狼人。

思路：遍历所有可能性，验证每一名参赛者的说法在这种假设下的真伪，如果结果刚好是N-3名平民说真话、1名狼人说真话，则满足要求。 

#include<iostream>
#include<vector>
#include<algorithm>
#include<set>
#include<map>
#include<cstring>
using namespace std;
const int MAX = 107;
int N;
int a[MAX];
bool W[MAX]={false};
bool judge(int x,int y){
	memset(W,false,sizeof(W));
	W[x]=true;W[y]=true;
	int humanCnt=0;int wolfCnt = 0;//说的真话 
	for(int i=1;i<=N;i++){
		if(!W[i]){//如果是平民 
			if((a[i]>0&&!W[a[i]])||(a[i]<0&&W[-a[i]])) humanCnt++;
		} 
		else{//如果是狼人 
			if((a[i]>0&&!W[a[i]])||(a[i]<0&&W[-a[i]])) wolfCnt++; 
		}
	}
	if(humanCnt==N-3&&wolfCnt==1) return true;
	else return false; 
}
int main(void){
	cin>>N;
	for(int i=1;i<=N;i++) cin>>a[i];
	for(int i=1;i<=N;i++){
		for(int j=i+1;j<=N;j++){
			if(judge(i,j)){
				cout<<i<<" "<<j;
				return 0;
			}
		}
	}
	cout<<"No Solution";
	return 0;
}