#include #include #include #include #include #define REP(i,a,b) for(i=a;i qu; set way[100005]; // root int distance_min = INT_MAX; int target; // 多分完成 void create_tree() { bool visited[100005] = {}; int node = 1; tree[node].depth = 0; visited[node] = true; qu.push(node); while( ! qu.empty() ) { node = qu.front(); qu.pop(); set::iterator itr = way[node].begin(); set::iterator past_itr = itr; for(; itr != way[node].end(); itr++) { if( ! visited[*itr] ) { tree[node].left = *itr; tree[*itr].depth = tree[node].depth+1; past_itr = itr; } } for(; itr != way[node].end(); itr++) { if( ! visited[*itr] ) { tree[*itr].depth = tree[node].depth+1; tree[*past_itr].right = *itr; past_itr = itr; } } itr--; tree[*itr].right = NIL; itr = way[node].begin(); for(; itr != way[node].end(); itr++) { if( ! visited[*itr] ) { visited[*itr] = true; qu.push(*itr); } } } } int distance_from_node_to_leef(int node) { if(tree[node].left == NIL) return 0; int distance[100005]; bool visited[100005] = {}; visited[node] = true; distance[node] = 0; qu.push(node); while( ! qu.empty() ) { node = qu.front(); qu.pop(); int child = tree[node].left; for(; child != NIL; child = tree[child].right) { if(tree[child].left == NIL) { return distance[node]+1; } else { distance[child] = distance[node]+1; qu.push(child); } } } } int main() { int i,j,k; int N; cin >> N; rep(i,N-1) { int x,y; scanf("%d %d",&x,&y); way[x].insert(y); way[y].insert(x); } rep(i,N+1) { tree[i].parent = NIL; tree[i].right = NIL; tree[i].left = NIL; } create_tree(); puts("0"); for(i=2;i qu; rep(i,waysize) { int& next = way[current_location][i]; if(next == target) { distance_min = min(cost,distance_min); } if(cost+1 > distance_min) break; seek_distance(next,cost+1); } } */