ThreeDisplays.cpp

// problem: https://codeforces.com/contest/987/problem/C

#include<bits/stdc++.h>

usingnamespacestd;

constlonglongint inf = 10000000000;

constint MAX = 3002;

longlongint lista[MAX];
longlongint custo[MAX];
longlongint dp[MAX][4];

longlongint c, a, ans;

int n;

longlongintbruto(int i, int ant, int rest){
if(rest == 0)
return0;
if(i == n+1)
return inf;

if(lista[i] > lista[ant]){
if(dp[i][rest] == inf)
 dp[i][rest] = bruto(i + 1, i, rest - 1) + custo[i];

 c = bruto(i + 1, ant, rest);

returnmin(dp[i][rest], c);
 } else
returnbruto( i + 1, ant, rest);
}

voidprep(){
for(int i = 0; i < n+2; i++)
for(int j = 0; j < 4; j++)
 dp[i][j] = inf;
}

intmain() {
ios_base::sync_with_stdio(false); cin.tie(0);
 cin >> n;
for(int i = 1; i < n+1; i++){
 cin >> a;
 lista[i] = a;
 }
for(int i = 1; i < n+1; i++){
 cin >> a;
 custo[i] = a;
 }
prep();

 ans = bruto(1, 0, 3);

if(ans < inf)
 cout << ans;
else
 cout << -1;

 cout << endl;
}