This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define fo(i, d, c) for (int i = d; i <= c; i++)
#define fod(i, c, d) for (int i = c; i >= d; i--)
#define maxn 1000010
#define N 5010
#define fi first
#define se second
#define pb emplace_back
#define en cout << "\n";
#define int long long
#define inf (int)1e18
#define pii pair<int, int>
#define vii vector<pii>
#define lb(x) x & -x
#define bit(i, j) ((i >> j) & 1)
#define offbit(i, j) (i ^ (1LL << j))
#define onbit(i, j) (i | (1LL << j))
#define vi vector<int>
template <typename T1, typename T2>
bool minimize(T1 &a, T2 b)
{
    if (a > b)
    {
        a = b;
        return true;
    }
    return false;
}
template <typename T1, typename T2>
bool maximize(T1 &a, T2 b)
{
    if (a < b)
    {
        a = b;
        return true;
    }
    return false;
}
using namespace std;
const int nsqrt = 450;
const int mod = 1e9 + 7;
int k,n,m,a,b,s[N],t[N],v[N];
namespace sub1
{
void solve()
{
    if(k != 1 or m > n) return;
    cout << m * v[1] ;
    exit(0);
}
}
namespace sub2
{
void solve()
{
    if(k != 1 or m <= n) return;
    cout << n * v[1] + (m - n) * b + a;
    exit(0);
}
}
namespace sub3
{
int f[N][N];
void solve()
{
    if(a != 0 or b != 0) return;
    int ans = 0;
    fo(i,1,n)
    {
        fo(j,1,m)
        {
            maximize(f[i][j],f[i - 1][j]);
            if(s[i] == t[j])
                maximize(f[i][j],f[i - 1][j - 1] + v[t[j]]);
        }
        fo(j,1,m) maximize(f[i][j],f[i][j - 1]);
        maximize(ans,f[i][m]);
    }
    cout << ans;
    exit(0);
}
}
namespace sub4
{
int f[N][N],dp[N][N];
void solve()
{
    if(a != 0) return;
    int ans = -inf;
    memset(f,-0x3f,sizeof f);
    memset(dp,-0x3f,sizeof dp);
    fo(i,1,n)
    {
        fo(j,1,m)
        {
            dp[i][j] = max(dp[i][j - 1] + b,dp[i - 1][j] + b);
            if(s[i] == t[j])
            {
                f[i][j] = max(dp[i - 1][j - 1] + v[t[j]],(j - 1) * b + v[t[j]]);
                maximize(dp[i][j],f[i][j]);
            }
            maximize(ans,f[i][j] + (m - j) * b);
        }
    }
    cout << ans;
    exit(0);
}
}
main()
{
#define name "TASK"
    if (fopen(name ".inp", "r"))
    {
        freopen(name ".inp", "r", stdin);
        freopen(name ".out", "w", stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> k >> n >> m >> a >> b;
    fo(i,1,k) cin >> v[i];
    fo(i,1,n) cin >> s[i];
    fo(i,1,m) cin >> t[i];
    sub1 :: solve();
    sub2 :: solve();
    sub3 :: solve();
    sub4 :: solve();
}
Compilation message (stderr)
VisitingSingapore.cpp:109:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  109 | main()
      | ^~~~
VisitingSingapore.cpp: In function 'int main()':
VisitingSingapore.cpp:114:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  114 |         freopen(name ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
VisitingSingapore.cpp:115:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  115 |         freopen(name ".out", "w", stdout);
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