Codeforces Round #254(div2)B

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<vector>
#include<algorithm>
#include<stack>
#include<queue>
using namespace std;
#define INF 1000000000
#define eps 1e-8
#define pii pair<int,int>
#define LL long long int
int n,m,maps[55][55],a,b;
int mark[55],num;
void dfs(int x)
{
    mark[x]=1;
    for(int i=1;i<=n;i++)
    {
        if(mark[i]==0&&maps[x][i])
        {
            dfs(i);
        }
    }
}
int main()
{
    //freopen("in1.txt","r",stdin);
    //freopen("out.txt","w",stdout);
    scanf("%d%d",&n,&m);
    for(int i=1;i<=m;i++)
    {
        scanf("%d%d",&a,&b);
        maps[a][b]=maps[b][a]=1;
    }
    for(int i=1;i<=n;i++)
    {
        if(!mark[i])
        {
            num++;
            dfs(i);
        }
    }
    printf("%I64d\n",(LL)1<<(n-num));
    //fclose(stdin);
    //fclose(stdout);
    return 0;
}