oj.uz

Submission #391671

# Submission time Handle Problem Language Result Execution time Memory
391671 2021-04-19T13:30:01 Z qwerasdfzxcl Lamps (JOI19_lamps) C++14
4 / 100
 42 ms 14164 KB 
#include <bits/stdc++.h>
 
typedef long long ll;
using namespace std;
string x, y;
int dp[1001000][3];
 
int calc(int n){
    int pt[2] = {-2, -2}, pt2=-2;
    if (x[0]!=y[0]) dp[0][0]=1, pt2=0;
    dp[0][1] = 1;
    pt[y[0]-'0']=0;
    for (int i=1;i<n;i++){
        if (x[i]==y[i]) dp[i][0]=min(dp[i-1][0], dp[i-1][1]);
        else{
            if (x[i-1]!=y[i-1]) dp[i][0] = min(dp[i-1][0], dp[i-1][1]+1);
            else if (pt2==-2) dp[i][0] = min(dp[i-1][0], dp[i-1][1])+1;
            else dp[i][0] = min(min(dp[i-1][0], dp[i-1][1]), dp[pt2][0])+1;
            pt2=i;
        }
        if (y[i-1]==y[i]) dp[i][1] = min(dp[i-1][1], dp[i-1][0]+1), pt[y[i]-'0']=i;
        else{
            if (pt[y[i]-'0']==-2) dp[i][1] = min(dp[i-1][0], dp[i-1][1])+1;
            else dp[i][1] = min(min(dp[i-1][0], dp[i-1][1]), dp[pt[y[i]-'0']][1])+1;
            pt[y[i]-'0']=i;
        }
    }
    /*for (int i=0;i<n;i++) cout << dp[i][0] << ' ';
    cout << '\n';
    for (int i=0;i<n;i++) cout << dp[i][1] << ' ';
    cout << '\n';*/
    return min(dp[n-1][0], dp[n-1][1]);
}
 
int main(){
    cin.tie(NULL);
    ios_base::sync_with_stdio(false);
    int n;
    cin >> n >> x >> y;
    int ans = calc(n);
    int pt1=-1, pt2=-1;
    for (int i=0;i<n;i++) if(x[i]!=y[i]){
        pt1=i; break;
    }
    for (int i=n-1;i>=0;i--) if(x[i]!=y[i]){
        pt2=i; break;
    }
    if (pt1!=-1){
        for (int i=pt1;i<=pt2;i++){
            if (x[i]=='0') x[i] = '1';
            else x[i] = '0';
        }
        ans = min(ans, calc(n)+1);
    }
    for (int j=0;j<2;j++){
        for (int i=0;i<n;i++) x[i] = '0'+j;
        ans = min(ans, calc(n)+1);
    }
    cout << ans;
    return 0;
}

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 208 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 208 KB Output is correct
12 Correct 1 ms 204 KB Output is correct
13 Incorrect 1 ms 204 KB Output isn't correct
14 Halted 0 ms 0 KB -

Subtask #2
0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 208 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 208 KB Output is correct
12 Correct 1 ms 204 KB Output is correct
13 Incorrect 1 ms 204 KB Output isn't correct
14 Halted 0 ms 0 KB -

Subtask #3
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 31 ms 14152 KB Output is correct
8 Correct 40 ms 14108 KB Output is correct
9 Correct 42 ms 14108 KB Output is correct
10 Correct 42 ms 14148 KB Output is correct
11 Correct 42 ms 14108 KB Output is correct
12 Correct 40 ms 14164 KB Output is correct
13 Correct 37 ms 14148 KB Output is correct
14 Correct 38 ms 14152 KB Output is correct

Subtask #4
0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 0 ms 208 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 208 KB Output is correct
12 Correct 1 ms 204 KB Output is correct
13 Incorrect 1 ms 204 KB Output isn't correct
14 Halted 0 ms 0 KB -