HDU1497 模拟

题意：模拟图书馆借书

book用于记录 该书 被那个学生借走了

pos 用于记录这本书被借走的同学放在了第几位.

注意：每次还书 的时候要更新pos！！！！

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<queue>
#include<stdlib.h>
#include<algorithm>
using namespace std;
const int maxn = 100005;
const int maxm = 1005;
int book[ maxn ],pos[ maxn ];
//int vis[ maxn ];
struct node{
    int book[ 12 ];
    int cnt;
}stu[ maxm ];
int main(){
    int m,n;
    while( scanf("%d%d",&m,&n)!=EOF ){
        for( int i=0;i<=m;i++ ){
            stu[ i ].cnt=0;
        }
        memset( book,-1,sizeof( book ));//book[ i ] the i people
        memset( pos,-1,sizeof( pos ));// pos[ k ] the kth place
        int ca;
        scanf("%d",&ca);
        for( int t=1;t<=ca;t++ ){
            char tmp[5];
            scanf("%s",&tmp);
            if( tmp[0]=='B' ){
                int u,b;
                scanf("%d%d",&u,&b);
                if( book[ b ]!=-1 ){
                    printf("The book is not in the library now\n");
                }
                else if( stu[ u ].cnt>=9 ){
                    printf("You are not allowed to borrow any more\n");
                }
                else {
                    stu[ u ].book[ stu[u].cnt ]=b;
                    pos[ b ]=stu[ u ].cnt;
                    book[ b ]=u;
                    stu[ u ].cnt++;
                    printf("Borrow success\n");
                }
            }
            else if( tmp[0]=='R' ){
                int b;
                scanf("%d",&b);
                if( book[ b ]==-1 ){
                    printf("The book is already in the library\n");
                }
                else {
                    printf("Return success\n");
                    for( int j=pos[b];j<stu[book[b]].cnt-1;j++ ){
                        stu[ book[b] ].book[ j ]=stu[ book[b] ].book[ j+1 ];
                        pos[ stu[ book[b] ].book[ j+1 ] ]=j;
                    }
                    
                    stu[ book[b] ].cnt--;
                    book[ b ]=-1;
                    pos[ b ]=-1;
                    
                }
            }
            else if( tmp[0]=='Q' ){
                int u;
                scanf("%d",&u);
                if( stu[ u ].cnt==0 ){
                    printf("Empty\n");
                }
                else {
                    int temp[ 12 ];
                    int k=0;
                    for( int i=0;;i++ ){
                        if( pos[stu[u].book[ i ]]!=-1 ){
                            temp[ k++ ]=stu[u].book[i];
                            if( k>=stu[u].cnt ) break;
                        }
                    }
                    sort( temp,temp+k );
                    for( int i=0;i<k;i++ ){
                        if( i==0 ) printf("%d",temp[i]);
                        else printf(" %d",temp[i]);
                    }
                    printf("\n");
                }
            }
        }
        printf("\n");
    }
    return 0;
}