UVA 336

#include <algorithm>
#include <cstdio>
#include <vector>
#include <queue>
using namespace std;
vector <int> ara[100000];

int bfs(int src, int leve, int node) {
    queue <int> q;
    q.push(src);
    int visited[32700] = {0}, level[32700]={0};
    visited[src] = 1;
    level[src] = 0;
    int ans = 0;
    while (!q.empty()) {
        int z = q.front();
        if (level[z] <= leve && level[z] != 0) ans++;
        if (level[z] > leve) {
            ans--;
            break;
        }
        for (int i = 0; i<ara[z].size(); i++) {
            int cur = ara[z][i];
            if (!visited[cur]) {
                level[cur] = level[z] + 1;
                visited[cur] = 1;
                q.push(cur);
            }
        }
        q.pop();
    }
    return node-ans-1;
}

int main() {

    int n, m, in1, in2, i,cs=0;
    while (scanf("%d", &n)) {
        if (n==0) return 0;

        int node=0;
        for (i=0; i<n; i++) {
            scanf("%d %d", &in1 , &in2);
            if (ara[in1].empty()) node++;
            else if (ara[in2].empty()) node++;
            ara[in1].push_back(in2);
            ara[in2].push_back(in1);
        }
        int x, y;

        while (scanf("%d %d", &x, &y)) {
            if (x == 0 && y==0) break;
            else printf("Case %d: %d nodes not reachable from node %d with TTL = %d.\n", ++cs, bfs(x, y, node), x, y);
        }

        for (int z=0; z<100000; z++) ara[z].clear();
    }
    return 0;
}