POJ2724 指令Windows Message Queue 优先队列

#include
#include
#include
#include
using namespace std;
struct Com
{
    char id[100];
    int q,priority,i;
    friend bool operator < (Com a,Com b)
    {
        if(a.priority == b.priority)
        return a.i > b.i;
        else return a.priority > b.priority;
    }
}z;
int main()
{
    int k;
    char type[4];
    k = 1;
    priority_queuep;
    while(scanf("%s",type)!=EOF)
    {
        if(strcmp(type,"GET") == 0)
        {
            if(p.empty())
            {
            printf("EMPTY QUEUE!\n");
            continue;
            }
            else 
            {
                printf("%s %d\n",p.top().id,p.top().q);
                p.pop();
            }
        }
        else if(strcmp(type,"PUT") == 0)
        {
            scanf("%s%d%d",z.id,&z.q,&z.priority);
            z.i = k;
            p.push(z);
            k++;
        }
    }
    return 0;
}





附上 网上别人博客的 东西  关于 priority 的写法有些不一样  


#include 
#include 
#include 
#include 
#include 
using namespace std;
struct node
{
    char s[100];
    int n;
    int p;
    int i;
};
struct cmp
{
    bool operator ()(const node&a,const node&b)
    {
        if(a.p==b.p)
        {
            return a.i>b.i;
        }
        return a.p>b.p;
    }
};
int main()
{
    node t;
    priority_queuevector,cmp> Q;
    char s[5];
    int k=1;
    while(scanf("%s",s)!=EOF)
    {
        if(s[0]=='G')
        {
            if(!Q.empty())
            {
                t=Q.top();
                Q.pop();
                printf("%s %d\n",t.s,t.n);
            }
            else
              printf("EMPTY QUEUE!\n");//开始时这忘记写'!'符号，贡献了次WA
        }
        else
        {
           scanf("%s%d%d",t.s,&t.n,&t.p);
             t.i=k++;
           Q.push(t);
        }
    }
    return 0;
}



另一种priority 不一样的写法   可以 研究一下  原理


#include 
#include 
#include 
#include 
#include 
#include 
using namespace std;
typedef struct MES{
    char str[25];
    int mes;
    int p;
    int ind;
};
bool operator<(MES a, MES b)
{
    if( a.p == b.p )
        return a.ind > b.ind;
    return a.p > b.p;
}
priority_queue q;
int main()
{
    char str[25];
    int ind = 0;
    MES tmp;
    while( ~scanf("%s",str) )
    {
        if( strcmp(str,"PUT") == 0 )
        {
            scanf("%s%d%d",tmp.str,&tmp.mes,&tmp.p);
            tmp.ind = ind++;
            q.push(tmp);
        }
        if( strcmp(str,"GET") == 0 )
        {
            if( q.empty() )
            {
                printf("EMPTY QUEUE!\n");
                continue;
            }
            tmp = q.top();
            q.pop();
            printf("%s %d\n",tmp.str,tmp.mes);
        }
    }
return 0;
}