CF161B Discounts

3 2
2 1
3 2
3 1

5.5
2 1 2
1 3

4 3
4 1
1 2
2 2
3 2

8.0
1 1
2 4 2
1 3

按照大小排下序,你會發現,如果按照從大到小的順序,那麼給凳子打折一定是最優的

於是,我們就可以找凳子打折,最後無論剩下多少都撂倒最後一個購物車裏

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <algorithm>
#define maxn 1200
#define rep(x,y,z) for(int x = y ; x <= z ; x ++)
using namespace std ;
struct dy{
    int c , t , id ;
}a[maxn] ;
int n , m , l , pos , num , sum , res , g[maxn] , s[maxn] , ans[maxn][maxn] , k;
bool book[maxn] ;
double money ;
int cmp(dy x , dy y) {
    return x.c > y.c ;
}  
int main() {
    scanf("%d%d",&n,&k) ;
    rep(i,1,n) {
        a[i].id = i ;
        scanf("%d%d",&a[i].c,&a[i].t) ;
        if(a[i].t == 1) res ++ ;
    }sort(a+1,a+1+n,cmp) ;
    rep(i,1,n) {
        if(k > 1 && a[i].t == 1) {
            k -- ;
            res -- ;
            book[i] = 1 ;
            ans[++num][++s[num]] = a[i].id ;
            money += 0.5*double(a[i].c) ;
            if(!res) break ;
        }
    }
    if(res) {
        rep(i,1,n) {
            if(book[i]) continue ;
            pos = i ;
            g[++sum] = a[i].id ;
            money += double(a[i].c) ;
        }
        money -= 0.5*double(a[pos].c) ;
    }else {
        rep(i,1,n) {
            if(book[i]) continue ;
            if(k > 1) {
                k -- ;
                ans[++num][++s[num]] = a[i].id ;
                money += double(a[i].c) ;
            }else {
                g[++sum] = a[i].id ;
                money += double(a[i].c) ;
            }
        }
    }
    printf("%.1lf\n",money) ;
    rep(i,1,num) {
        printf("%d ",s[i]) ;
        rep(j,1,s[i]-1) {
            printf("%d ",ans[i][j]) ;
        }printf("%d\n",ans[i][s[i]]) ;
    }
    if(!sum) return 0 ;
    printf("%d " , sum ) ;
    rep(i,1,sum-1) {
        printf("%d ",g[i]) ;
    }printf("%d\n",g[sum]) ;
    return 0 ;
}