Submission #105863

#	Time	Username	Problem	Language	Result	Execution time	Memory
105863		Alexa2001	Lamps (JOI19_lamps)	C++17	0 / 100	1070 ms	22344 KiB

lamp

#include <bits/stdc++.h>

using namespace std;

const int Nmax = 1e6 + 5;

int a[Nmax], b[Nmax], a0[Nmax], b0[Nmax], ones[Nmax], dp[Nmax];
int i, j, n;

int nr_ones(int x, int y)
{
    return ones[y] - ones[x-1];
}

int main()
{
  //  freopen("input", "r", stdin);
    cin.sync_with_stdio(false);

    cin >> n;
    string A, B;
    cin >> A >> B;

    for(i=1; i<=n; ++i)
        a0[i] = A[i-1] - '0', b0[i] = B[i-1] - '0';

    for(i=1; i<=n+1; ++i)
        a[i] = a0[i-1] ^ a0[i], b[i] = b0[i-1] ^ b0[i];

    for(i=1; i<=n+1; ++i) ones[i] = ones[i-1] + b[i];

    for(i=1; i<=n+1; ++i)
    {
        dp[i] = dp[i-1] + (a[i] ^ b[i]);

        for(j=1; j<i; ++j) /// flip cu schimbare j...i
            dp[i] = min(dp[i], dp[j-1] + 2 + (a[i] ^ b[i] ^ 1) + (a[j] ^ b[j] ^ 1) + nr_ones(j+1, i) );
    }

    cout << (dp[n+1] + 1)/2 << '\n';
    return 0;
}

• Subtask 1: 0 / 6
• Subtask 2: 0 / 41
• Subtask 3: 0 / 4
• Subtask 4: 0 / 49