zoukankan      html  css  js  c++  java
  • CF DIV 2 206 C. Vasya and Robot

    C. Vasya and Robot
    time limit per test
    1 second
    memory limit per test
    256 megabytes
    input
    standard input
    output
    standard output

    Vasya has n items lying in a line. The items are consecutively numbered by numbers from 1 to n in such a way that the leftmost item has number 1, the rightmost item has number n. Each item has a weight, the i-th item weights wi kilograms.

    Vasya needs to collect all these items, however he won't do it by himself. He uses his brand new robot. The robot has two different arms — the left one and the right one. The robot can consecutively perform the following actions:

    1. Take the leftmost item with the left hand and spend wi · l energy units (wi is a weight of the leftmost item, l is some parameter). If the previous action was the same (left-hand), then the robot spends extra Ql energy units;
    2. Take the rightmost item with the right hand and spend wj · r energy units (wj is a weight of the rightmost item, r is some parameter). If the previous action was the same (right-hand), then the robot spends extra Qr energy units;

    Naturally, Vasya wants to program the robot in a way that the robot spends as little energy as possible. He asked you to solve this problem. Your task is to find the minimum number of energy units robot spends to collect all items.

    Input

    The first line contains five integers n, l, r, Ql, Qr (1 ≤ n ≤ 105; 1 ≤ l, r ≤ 100; 1 ≤ Ql, Qr ≤ 104).

    The second line contains n integers w1, w2, ..., wn (1 ≤ wi ≤ 100).

    Output

    In the single line print a single number — the answer to the problem.

    Sample test(s)
    input
    3 4 4 19 1
    42 3 99
    output
    576
    input
    4 7 2 3 9
    1 2 3 4
    output
    34
    Note

    Consider the first sample. As l = r, we can take an item in turns: first from the left side, then from the right one and last item from the left. In total the robot spends 4·42 + 4·99 + 4·3 = 576 energy units.

    The second sample. The optimal solution is to take one item from the right, then one item from the left and two items from the right. In total the robot spends (2·4) + (7·1) + (2·3) + (2·2 + 9) = 34 energy units.

     枚举n个物品里面有多少个是用左手拿的。。。。

    /*
     * Author:  
     * Created Time:  2013/10/14 15:09:49
     * File Name: A.cpp
     * solve: A.cpp
     */
    #include<cstdio>
    #include<cstring>
    #include<cstdlib>
    #include<cmath>
    #include<algorithm>
    #include<string>
    #include<map>
    #include<stack>
    #include<set>
    #include<iostream>
    #include<vector>
    #include<queue>
    //ios_base::sync_with_stdio(false);
    //#pragma comment(linker, "/STACK:1024000000,1024000000")
    
    using namespace std;
    #define sz(v) ((int)(v).size())
    #define rep(i, a, b) for (int i = (a); i < (b); ++i)
    #define repf(i, a, b) for (int i = (a); i <= (b); ++i)
    #define repd(i, a, b) for (int i = (a); i >= (b); --i)
    #define clr(x) memset(x,0,sizeof(x))
    #define clrs( x , y ) memset(x,y,sizeof(x))
    #define out(x) printf(#x" %d
    ", x)
    #define sqr(x) ((x) * (x))
    typedef long long LL;
    
    const LL INF = 10000000000000;
    const double eps = 1e-8;
    const int maxn = 100100;
    
    int sgn(const double &x) {  return (x > eps) - (x < -eps); }
    LL sum[maxn];
    LL w[maxn];
    LL n,l,r,ql,qr;
    LL cal(LL num)
    {
        LL L = num;
        LL R = n - L;
        LL ans = 0;
        ans += l*sum[L];
        ans += r*(sum[n] - sum[L]);
        if(R > L)
        {
            ans += (R - L - 1)*qr;
        }else if(R < L)
            ans += (L - R - 1)*ql;
        return ans;
    }
    int main() 
    {
        //freopen("in.txt","r",stdin);
        scanf("%I64d%I64d%I64d%I64d%I64d",&n,&l,&r,&ql,&qr);
        
        sum[0] = 0;
        repf(i,1,n)
        {
            scanf("%I64d",&w[i]);
            sum[i] = sum[i-1] + w[i];
        }
        
        LL ans = INF;
        repf(i,0,n)
            ans = min(ans,cal(i));
        cout<<ans<<endl;
        
        return 0;
    }
  • 相关阅读:
    叨叨叨
    四舍五入VS银行家舍入
    是雏还是鹰&mdash;&mdash;编程规范之变量命名
    .Net下二进制形式的文件(图片)的存储与读取(原创)
    asp.net中<%%>形式的用法(原创)
    让Hashtable支持自定义排序(原创)
    .NET下的迭代器(Iterator)模式
    本地视频播放-ios
    cocos2dx srand(time(NULL))重新设置一个随机种子
    cocos2dx 游戏重置方法
  • 原文地址:https://www.cnblogs.com/DreamHighWithMe/p/3369259.html
Copyright © 2011-2022 走看看