loj1185.cpp

/*
Author: Golam Rahman Tushar
........Aust Cse 27th batch.........
*/

//{ Template

//{ C-headers
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <climits>
#include <cfloat>
#include <cctype>
#include <cassert>
#include <ctime>
//}
//{ C++-headers
#include <iostream>
#include <iomanip>
#include <sstream>
#include <algorithm>
#include <utility>
#include <string>
#include <stack>
#include <queue>
#include <vector>
#include <set>
#include <map>

using namespace std;
//}

//}
//{ Floating-points
#define EPS DBL_EPSILON
#define abs(x) (((x) < 0) ? - (x) : (x))
#define zero(x) (abs (x) < EPS)
#define equal(a,b) (zero ((a) - (b)))
#define PI 2 * acos (0.0)
//}

#define INF 1<<29
#define ll long long

template <typename T>
std::string to_string(T const& value) {
    stringstream sstr;
    sstr << value;
    return sstr.str();
}
//}

template <class T> T gcd(T a,T b){if(b==0) return a;else return gcd(b,a%b);}
template <class T> T lcm(T a,T b){return (a*b)/gcd(a,b);}
template <class T> T power( T a, T b){if(b==0) return 1; T x=a;for(T i=2;i<=b;i++) a=a*x;return a;}
template <class T> T BigMod(T a,T b,T c){if(a==0) return 0;if(b==0) return 1;if(b%2==0){T x=BigMod(a,b/2,c)%c;return (x*x)%c;}else return  ((a%c)*BigMod(a,b-1,c)%c)%c;}

#define mx 107

vector<int>graph[5000+7];
bool visited[mx], ans[mx];

void bfs()
{
    queue<int>q;
    q.push(0);

    while(!q.empty()) {
        int u = q.front();
        q.pop();

        for(int i=0;i<graph[u].size();i++) {
            int v = graph[u][i];
            bool dukse = 0;
            if(visited[u]&&!ans[v]) ans[v] = dukse = 1;
            if(!visited[v]&&(u==0||ans[u])) visited[v] = dukse = 1;

            if(dukse) q.push(v);
        }
    }
}
int main ()
{
    //freopen("input.txt","r",stdin);
    int t, u, v, i, n, m, cnt, Case = 1;
    scanf("%d",&t);

    while(t--) {


        scanf("%d %d",&n,&m);
        for(i=0;i<m;i++) {
            scanf("%d %d",&u, &v);
            u--; v--;
            graph[u].push_back(v);
            graph[v].push_back(u);
        }

        for(i=0;i<=n;i++) visited[i] = ans[i] = 0;
        bfs();

        cnt = 0;
        for(i=0;i<n;i++) if(ans[i]) cnt++;
        printf("Case %d: %d\n",Case++,cnt);

        for(i=0;i<=n;i++) graph[i].clear();
    }
    return 0;
}