#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll N = 505, oo = 1e18+10;
ll dp[N][N][2], save_dp[N][N][2], x[N], t[N];
ll n, s;
ll dist(ll i, ll j) {
if(x[i] > x[j]) {
swap(i, j);
}
return min(x[j] - x[i], x[i] + s - x[j]);
}
int main() {
ios::sync_with_stdio(0); cin.tie(0);
cin >> n >> s;
for(int i = 1; i <= n; ++i) {
cin >> x[i];
}
for(int i = 1; i <= n; ++i) {
cin >> t[i];
}
for(int i = n+2; i <= 2*n+1; ++i) {
x[i] = x[i - n - 1];
t[i] = t[i - n - 1];
}
for(int i = 0; i < N; ++i) {
for(int j = 0; j < N; ++j) {
save_dp[i][j][0] = save_dp[i][j][1] = oo;
dp[i][j][0] = dp[i][j][1] = oo;
}
}
save_dp[n+1][n+1][0] = save_dp[n+1][n+1][1] = 0;
ll ans = 0;
auto mini = [](ll &x, ll y) {
x = min(x, y);
};
for(int X = 2; X <= n+1; ++X) {
for(int R = n+1; R <= 2*n+1; ++R) {
for(int L = n+1; L >= R-n; --L) {
ll &bestL = dp[L][R][0];
ll &bestR = dp[L][R][1];
if(L < n + 1) {
ll opt0 = min(save_dp[L+1][R][0] + dist(L, L+1), save_dp[L+1][R][1] + dist(L, R));
if(opt0 <= t[L]) mini(bestL, opt0);
mini(bestL, dp[L+1][R][0] + dist(L, L+1));
mini(bestL, dp[L+1][R][1] + dist(L, R));
}
if(R > n + 1) {
ll opt0 = min(save_dp[L][R-1][1] + dist(R-1, R), save_dp[L][R-1][0] + dist(L, R));
if(opt0 <= t[R]) mini(bestR, opt0);
mini(bestR, dp[L][R-1][1] + dist(R-1, R));
mini(bestR, dp[L][R-1][0] + dist(L, R));
}
if(bestL < oo || bestR < oo) {
ans = X;
}
}
}
swap(dp, save_dp);
for(int i = 0; i < N; ++i) {
for(int j = 0; j < N; ++j) {
for(int k = 0; k < 2; ++k) {
dp[i][j][k] = oo;
}
}
}
}
cout << ans-1 << endl;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
8268 KB |
Output is correct |
2 |
Correct |
9 ms |
8268 KB |
Output is correct |
3 |
Incorrect |
13 ms |
8308 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
8268 KB |
Output is correct |
2 |
Correct |
9 ms |
8268 KB |
Output is correct |
3 |
Incorrect |
13 ms |
8308 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
8268 KB |
Output is correct |
2 |
Correct |
9 ms |
8268 KB |
Output is correct |
3 |
Incorrect |
13 ms |
8308 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
8268 KB |
Output is correct |
2 |
Correct |
9 ms |
8268 KB |
Output is correct |
3 |
Incorrect |
13 ms |
8308 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |