Team Queue |
Queues and Priority Queues are data structures which are known to most computer scientists. The Team Queue, however, is not so well known, though it occurs often in everyday life. At lunch time the queue in front of the Mensa is a team queue, for example.
In a team queue each element belongs to a team. If an element enters the queue, it first searches the queue from head to tail to check if some of its teammates (elements of the same team) are already in the queue. If yes, it enters the queue right behind them. If not, it enters the queue at the tail and becomes the new last element (bad luck). Dequeuing is done like in normal queues: elements are processed from head to tail in the order they appear in the team queue.
Your task is to write a program that simulates such a team queue.
Finally, a list of commands follows. There are three different kinds of commands:
The input will be terminated by a value of 0 for t.
Warning: A test case may contain up to 200000 (two hundred thousand) commands, so the implementation of the team queue should be efficient: both enqueing and dequeuing of an element should only take constant time.
2 3 101 102 103 3 201 202 203 ENQUEUE 101 ENQUEUE 201 ENQUEUE 102 ENQUEUE 202 ENQUEUE 103 ENQUEUE 203 DEQUEUE DEQUEUE DEQUEUE DEQUEUE DEQUEUE DEQUEUE STOP 2 5 259001 259002 259003 259004 259005 6 260001 260002 260003 260004 260005 260006 ENQUEUE 259001 ENQUEUE 260001 ENQUEUE 259002 ENQUEUE 259003 ENQUEUE 259004 ENQUEUE 259005 DEQUEUE DEQUEUE ENQUEUE 260002 ENQUEUE 260003 DEQUEUE DEQUEUE DEQUEUE DEQUEUE STOP 0
Scenario #1 101 102 103 201 202 203 Scenario #2 259001 259002 259003 259004 259005 260001
题目大意:有n组人排队,输入n行,每行第一个数字代表该组所有的人数的序号。然后输入命令ENQUEUE代表入队,如果前面的队伍中有和自己同一组的,要直接插在同组人的后面,否则放在队末。DEQUEUE代表出队,站在第一个的要离开队伍。STOP中指命令。按顺序输出出队人的序号。
解题思路:模拟的方法。用queue的数组模拟排队的情况。
#include<iostream> #include<string.h> #include<queue> using namespace std; #define N 1000005 #define M 1005 int p[N]; int now[N]; int cnt_now; int sex[M]; int main() { int t = 1; int n; while(cin >> n, n) { // Init. memset(p, 0, sizeof(p)); memset(now, 0, sizeof(now)); memset(sex, 0, sizeof(sex)); cnt_now = 0; // Read. for(int i = 1; i <= n; i++) { int sum; cin >> sum; for(int j = 0; j < sum; j++) { int f; cin >> f; p[f] = i; } } int first = 0; queue<int> team[M]; char str[10]; int num; int move; while(cin >> str) { if( strcmp( str, "STOP") == 0) break; else if( strcmp( str, "DEQUEUE" ) == 0) { now[cnt_now++] = team[first].front(); team[first].pop(); if(team[first].empty()) { sex[first] = 0; first++; } } else { if(first >= M) first = first % M; cin >> num; for(move = first; ; move++) { if(move >= M ) move = move % M; if(sex[move] == p[num]) break; else if(sex[move] == 0) break; } team[move].push(num); sex[move] = p[num]; } } cout <<"Scenario #" << t++ << endl; for(int i = 0; i < cnt_now; i++) cout << now[i] << endl; cout << endl; } return 0; }