题意
分析
代码
#include <iostream>
#include <cstring>
#include <algorithm>
#define MP make_pair
#define PB emplace_back
#define fi first
#define se second
#define ZERO(x) memset((x), 0, sizeof(x))
#define ALL(x) (x).begin(),(x).end()
#define rep(i, a, b) for (repType i = (a); i <= (b); ++i)
#define per(i, a, b) for (repType i = (a); i >= (b); --i)
#define QUICKIO ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
using namespace std;
typedef long long ll;
typedef int repType;
const int MAXN=130;
bool mat[MAXN][MAXN];
int n,m,ans;
int done[MAXN][MAXN], notyet[MAXN][MAXN], searched[MAXN][MAXN];
void dfs(int n, int dcnt, int ncnt, int scnt)
{
if(!ncnt && !scnt) ans++;
if(ans>1000) return;
int key=notyet[n][1];
rep(j,1,ncnt)
{
int v=notyet[n][j], tmp_ncnt=0, tmp_scnt=0;
if(mat[key][v]) continue;
memcpy(done[n+1],done[n],sizeof(int)*(dcnt+1));
done[n+1][dcnt+1]=v;
rep(i,1,ncnt) if(mat[v][notyet[n][i]])
notyet[n+1][++tmp_ncnt]=notyet[n][i];
rep(i,1,scnt) if(mat[v][searched[n][i]])
searched[n+1][++tmp_scnt]=searched[n][i];
dfs(n+1, dcnt+1, tmp_ncnt, tmp_scnt);
notyet[n][j]=0;
searched[n][++scnt]=v;
}
}
int main()
{
while(cin>>n>>m)
{
ZERO(mat); ans=0;
rep(i,1,m)
{
int x,y;
cin>>x>>y;
mat[x][y]=mat[y][x]=true;
}
rep(i,1,n) notyet[1][i]=i;
dfs(1,0,n,0);
if(ans>1000) cout<<"Too many maximal sets of friends."<<endl;
else cout<<ans<<endl;
}
return 0;
}
原文地址:https://www.cnblogs.com/samhx/p/POJ-2989.html
时间: 2024-11-08 21:27:39