#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pl;
typedef pair<int,int> pii;
typedef tuple<int,int,int> tt;
#define all(a) a.begin(), a.end()
#define filter(a) a.erase(unique(all(a)), a.end())
int dp[503][503][503][3], onePos[503];
int main()
{
ios::sync_with_stdio(0);
cin.tie(0);
int n, k; cin >> n >> k;
string s; cin >> s;
s = " " + s;
/// pre-calculations
int zeroCount = 0, oneCount = 0;
for (int i = 1; i <= n; i++) {
if (s[i] == '1') onePos[++oneCount] = i;
else zeroCount++;
}
/// setup base-cases
for (int diff = 0; diff <= n; diff++)
for (int i = 0; i <= zeroCount; i++)
for (int j = 0; j <= oneCount; j++)
for (int last = 0; last < 2; last++) dp[diff][i][j][last] = INT_MAX;
dp[0][0][0][0] = dp[0][0][0][1] = 0;
/// run DP
for (int diff = 1; diff <= n; diff++) {
for (int zCur = 0; zCur <= zeroCount; zCur++) {
for (int oCur = 0; oCur <= oneCount; oCur++) {
if (!zCur && !oCur) continue;
// calculate dp[diff][zCur][oCur][1]
if (oCur) {
int oldPos = onePos[oCur], newPos = zCur + oCur, cost = abs(oldPos - newPos);
if (diff) { // place a '0' before it
int recur = dp[diff - 1][zCur][oCur - 1][0];
if (recur != INT_MAX)
dp[diff][zCur][oCur][1] = min(dp[diff][zCur][oCur][1], recur + cost);
}
if (true) { // place a '1' before it
int recur = dp[diff][zCur][oCur - 1][1];
if (recur != INT_MAX)
dp[diff][zCur][oCur][1] = min(dp[diff][zCur][oCur][1], recur + cost);
}
}
// calculate dp[diff][zCur][oCur][0]
if (zCur) {
if (diff) { // place a '1' before it
dp[diff][zCur][oCur][0] = min(dp[diff][zCur][oCur][0], dp[diff - 1][zCur - 1][oCur][1]);
}
if (true) { // place a '0' before it
dp[diff][zCur][oCur][0] = min(dp[diff][zCur][oCur][0], dp[diff][zCur - 1][oCur][0]);
}
}
}
}
}
int ans = 0;
for (int diff = 2; diff <= n; diff++) {
//cout << diff << " " << dp[diff][zeroCount][oneCount][0] << " " << dp[diff][zeroCount][oneCount][1] << "\n";
if (min(dp[diff][zeroCount][oneCount][0], dp[diff][zeroCount][oneCount][1]) <= k) ans = diff - 1;
}
cout << ans;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2384 KB |
Output is correct |
2 |
Correct |
1 ms |
4432 KB |
Output is correct |
3 |
Correct |
1 ms |
6480 KB |
Output is correct |
4 |
Incorrect |
4 ms |
20816 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2384 KB |
Output is correct |
2 |
Correct |
1 ms |
4432 KB |
Output is correct |
3 |
Correct |
1 ms |
6480 KB |
Output is correct |
4 |
Incorrect |
4 ms |
20816 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
6480 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2384 KB |
Output is correct |
2 |
Correct |
1 ms |
4432 KB |
Output is correct |
3 |
Correct |
1 ms |
6480 KB |
Output is correct |
4 |
Incorrect |
4 ms |
20816 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |