Codeforces Round #345 (Div. 2) B. Beautiful Paintings __ greedy and Bucket_sort

B. Beautiful Paintings
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

There are n pictures delivered for the new exhibition. The i-th painting has beauty ai. We know that a visitor becomes happy every time he passes from a painting to a more beautiful one.

We are allowed to arranged pictures in any order. What is the maximum possible number of times the visitor may become happy while passing all pictures from first to last? In other words, we are allowed to rearrange elements of a in any order. What is the maximum possible number of indices i (1 ≤ i ≤ n - 1), such that ai + 1 > ai.

Input

The first line of the input contains integer n (1 ≤ n ≤ 1000) — the number of painting.

The second line contains the sequence a1, a2, ..., an (1 ≤ ai ≤ 1000), where ai means the beauty of the i-th painting.

Output

Print one integer — the maximum possible number of neighbouring pairs, such that ai + 1 > ai, after the optimal rearrangement.

Examples
input
5
20 30 10 50 40
output
4
input
4
200 100 100 200
output
2
Note

In the first sample, the optimal order is: 10, 20, 30, 40, 50.

In the second sample, the optimal order is: 100, 200, 100, 200.

Source

Codeforces Round #345 (Div. 2) B. Beautiful Paintings



My Solution
greedy and Bucket_sort.
I use bool Bucket_sort[maxn][maxn] to store the k sequences,like
1 2 3 4 5 6 7 8 9 10
        1 2 3 4 5 6 7 8
        1 2 3 4 5 
        1    3    5
1          5
              3
        etc.

Please see my code for details

#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
const int maxn = 1000 + 8;
bool Bucket_sort[maxn][maxn];


int main()
{
    memset(Bucket_sort, false, sizeof Bucket_sort);
    int n, a, ans = 0;
    scanf("%d", &n);
    //WA13  1 <= ai <= 1000 so i = 1 to 1000  ,  not the first time I did i = 0 to 999
    while(n--){
        scanf("%d", &a);
        for(int i = 1; i <= 1000; i++)
            if(!Bucket_sort[i][a]) {Bucket_sort[i][a] = true; break;}
    }
    int pairnum;
    for(int i = 1; i <= 1000; i++){
        pairnum = 0;
        for(int j = 1; j <= 1000; j++){
            if(Bucket_sort[i][j]) pairnum++;
        }
        //cout<<pairnum<<endl;
        if(pairnum > 1)ans += pairnum - 1;     //we need to add this "if(pairnum > 1)"
    }
    printf("%d", ans);
    return 0;
}


Thank you all !☺☺
      

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