Description
Message queue is the basic fundamental of windows system. For each process, the system maintains a message queue. If something happens to this process, such as mouse click, text change, the system will add a message to the queue. Meanwhile, the process will
do a loop for getting message from the queue according to the priority value if it is not empty. Note that the less priority value means the higher priority. In this problem, you are asked to simulate the message queue for putting messages to and getting message
from the message queue.
Output
For each "GET" command, output the command getting from the message queue with the name and parameter in one line. If there's no message in the queue, output "EMPTY QUEUE!". There's no output for "PUT" command.
Sample Output
EMPTY QUEUE!
msg2 10
msg1 10
EMPTY QUEUE!
#include <iostream>
#include <string>
#include <queue>
using namespace std;
struct node
{string a;
int b,c,d;
bool friend operator<(node n1,node n2)
{
if(n1.c==n2.c)return n1.d>n2.d;
return n1.c >n2.c;
}
}s;
int main()
{ priority_queue<node>q;
string a1;
int k=1;
while(cin>>a1)
{if(a1[0]=='G')
{if(!q.empty())
{s=q.top();
q.pop();
cout<<s.a<<" "<<s.b<<endl;}
else cout<<"EMPTY QUEUE!"<<endl;
}
else {cin>>s.a>>s.b>>s.c;
s.d=k++;
q.push(s);}
}
return 0;}