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,你会发现,如果按照从大到小的顺序,那么给凳子打折一定是最优的

于是,我们就可以找凳子打折,最后无论剩下多少都撂倒最后一个购物车里

#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 ;
}