UVa - 336 - A Node Too Far!

#include <iostream>
#include <cstring>
#include <vector>
#include <queue>
#define M 100003
using namespace std;

vector <int> node[M];
int cs = 1, mx, cnt;

void bfs(int src, int TTL, int cnt){
    queue <int> container;
    int visited[M] = {0}, ans = 1, power[M] = {0};
    visited[src] = 1;
    container.push(src);
    while(!container.empty()){
        int u = container.front();
        int sz = node[u].size();
        for(int i = 0; i < sz; i++){
            int v = node[u][i];
            if(!visited[v]){
                visited[v] = 1;
                power[v] = power[u]+1;
                if(power[v] <= TTL)ans++;
                container.push(v);
            }
        }
        container.pop();
    }
    cout << "Case " << cs << ": " << (cnt - ans) << " nodes not reachable from node " << src << " with TTL = " << TTL << "." << endl;
}

int main(){
    int N, E, x, y, src, TTL, m, num[M] = {0};
    while(cin >> N ){
        mx = 0, cnt = 0;
        if(!N)break;
        for(int i = 0; i < N; i++){
            cin >> x >> y,node[x].push_back(y), node[y].push_back(x);
            m = max(x, y);
            mx = max(mx, m);
        }
        for(int i = 0; i < mx+1; i++){
            int sz = node[i].size();
            if(sz > 0)cnt++;
        }
        while(cin >> src >> TTL){
            if(!src && !TTL)break;
            bfs(src, TTL, cnt);
            cs++;
        }
        for(int i = 0; i <= M; i++)node[i].clear();
    }
    return 0;
}