Professor Dumbledore is helping Harry destroy the Horcruxes. He went to Gaunt Shack as he suspected a Horcrux to be present there. He saw Marvolo Gaunt‘s Ring and identified it as a Horcrux. Although he destroyed it, he is still affected by its curse. Professor Snape is helping Dumbledore remove the curse. For this, he wants to give Dumbledore exactly x drops of the potion he made.
Value of x is calculated as maximum of p·ai + q·aj + r·ak for given p, q, r and array a1, a2, ... an such that 1 ≤ i ≤ j ≤ k ≤ n. Help Snape find the value of x. Do note that the value of x may be negative.
Input
First line of input contains 4 integers n, p, q, r ( - 109 ≤ p, q, r ≤ 109, 1 ≤ n ≤ 105).
Next line of input contains n space separated integers a1, a2, ... an ( - 109 ≤ ai ≤ 109).
Output
Output a single integer the maximum value of p·ai + q·aj + r·ak that can be obtained provided 1 ≤ i ≤ j ≤ k ≤ n.
Examples
Input
5 1 2 31 2 3 4 5
Output
30
Input
5 1 2 -3-1 -2 -3 -4 -5
Output
12
Note
In the first sample case, we can take i = j = k = 5, thus making the answer as 1·5 + 2·5 + 3·5 = 30.
In second sample case, selecting i = j = 1 and k = 5 gives the answer 12.
#include <iostream> #include <algorithm> #include <cstdio> #include <string> #include <cstring> #include <cstdlib> #include <map> #include <vector> #include <set> #include <queue> #include <stack> #include <cmath> typedef long long lli; using namespace std; const int mxn = 1e9; #define TLE std::ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); cout.precision(10); multiset<int> v; multiset<int> :: iterator it ; int main() { TLE; lli n,cnt=1,m,k,ll; while(cin>>n>>m>>k>>ll) { int flag1 = 0,flag2=0;lli mx,x; if(m>=0 && k>=0 && ll>=0 ) flag1=1; if(m<0 && k<0 && ll<0 ) flag2=1; if(flag1) { cin>>mx; for(int i=2; i<=n; i++) { cin>>x; mx = max( mx ,x ); } cout<<(m+k+ll)*mx<<endl; } else if(flag2) { cin>>mx; for(int i=2; i<=n; i++) { cin>>x; mx = min( mx ,x ); } cout<<(m+k+ll)*mx<<endl; } else { lli dp[n+5]; lli l[n+5],r[n+5]; for(int i=1;i<=n;i++) { cin>>dp[i]; } l[1] = m*dp[1]; for(int i=2; i<=n; i++) { l[i] = max( l[i-1] ,m*dp[i] ); } r[n] = ll*dp[n]; for(int i=n-1; i>=1; i--) { r[i] = max( r[i+1] , ll*dp[i] ); } mx = -1000000000000000000000-5; for(int i=1; i<=n; i++) mx = max( l[i]+r[i]+dp[i]*k , mx); cout<<mx<<endl; } } return 0; }
B Marvolo Gaunt's Ring
原文地址:https://www.cnblogs.com/Shallow-dream/p/11623521.html