Educational Codeforces Round 30 A[水题/数组排序]

最新推荐文章于 2025-03-22 21:51:30 发布

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最新推荐文章于 2025-03-22 21:51:30 发布

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原文链接：http://www.cnblogs.com/Roni-i/p/7662923.html

本文介绍了一个简单的贪心算法，用于解决如何最有效地安排一系列家务任务的问题。通过选择部分任务用固定时间完成来最小化总耗时。输入包括任务数量、可加速的任务数及加速时间等参数。

Luba has to do n chores today. i-th chore takes ai units of time to complete. It is guaranteed that for every $\text{[math]}$ the conditionai ≥ ai - 1 is met, so the sequence is sorted.

Also Luba can work really hard on some chores. She can choose not more than k any chores and do each of them in x units of time instead of ai ( $\text{[math]}$ ).

Luba is very responsible, so she has to do all n chores, and now she wants to know the minimum time she needs to do everything. Luba cannot do two chores simultaneously.

Input

The first line contains three integers n, k, x (1 ≤ k ≤ n ≤ 100, 1 ≤ x ≤ 99) — the number of chores Luba has to do, the number of chores she can do in x units of time, and the number x itself.

The second line contains n integer numbers ai (2 ≤ ai ≤ 100) — the time Luba has to spend to do i-th chore.

It is guaranteed that $\text{[math]}$ , and for each $\text{[math]}$ ai ≥ ai - 1.

Output

Print one number — minimum time Luba needs to do all n chores.

Examples

input

4 2 2
3 6 7 10

output

input

5 2 1
100 100 100 100 100

output

Note

In the first example the best option would be to do the third and the fourth chore, spending x = 2 time on each instead of a3 and a4, respectively. Then the answer is 3 + 6 + 2 + 2 = 13.

In the second example Luba can choose any two chores to spend x time on them instead of ai. So the answer is 100·3 + 2·1 = 302.

【分析】：傻逼贪心。控制前n-k个数组求本位和，其他换成k求和。

【代码】：

#include <bits/stdc++.h>

using namespace std;

int main()
{
    int n,k,x;
    int a[105];
    while(~scanf("%d%d%d",&n,&k,&x))
    {
        for(int i=0;i<n;i++)
        {
            scanf("%d",&a[i]);
        }
        int sum=0;
        for(int i=0;i<n-k;i++)
        {
            sum+=a[i];
        }
        for(int i=n-k+1;i<=n;i++)
        {
            sum+=x;
        }
        printf("%d\n",sum);
    }
    return 0;
}

View Code

#pragma GCC optimize(3)
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
inline void readInt(int &x) {
    x=0;int f=1;char ch=getchar();
    while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
    while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
    x*=f;
}
inline void readLong(ll &x) {
    x=0;int f=1;char ch=getchar();
    while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
    while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
    x*=f;
}
/*================Header Template==============*/
int n,a,ans=0,k,x;
int main() {
    readInt(n);
    readInt(k);
    readInt(x);
    for(int i=1;i<=n;i++) {
        readInt(a);
        if(i<=n-k)
            ans+=a;
        else
            ans+=x;
    }
    printf("%d\n",ans);
    return 0;
}