Submission #1150991

#	Time	Username	Problem	Language	Result	Execution time	Memory
1150991		weakweakweak	Lamps (JOI19_lamps)	C++20	0 / 100	5 ms	4500 KiB

lamp

#include <bits/stdc++.h>
using namespace std;

int n;
string a, b;
int dp[2100][2][2] = {0};

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0);
    cin >> n >> a >> b;
    for (char &c : a) c -= '0';
    for (char &c : b) c -= '0';
    a = "$"+a, b = "$"+b;
    memset(dp, 63, sizeof(dp));
    dp[0][0][0] = 0;

    for (int i = 1; i <= n; i++) {
        if (a[i] == b[i]) {
            int z = min(dp[i-1][1][0], dp[i-1][0][0]);
            z = min(z, min(dp[i-1][1][1], dp[i-1][0][1]));
            dp[i][0][0] = min(dp[i][0][0], z);
        }
        else {
            int z = min(dp[i-1][1][0], dp[i-1][0][0]);
            z = min(z, min(dp[i-1][1][1], dp[i-1][0][1]));
            dp[i][0][0] = min(dp[i][0][0], z+1);
        }
        if (b[i] == 0) {
            for (int j = i; j <= n and b[j] == 0; j++) dp[j][1][0] = min(dp[j][1][0], min(dp[i-1][0][0], dp[i-1][1][0]) + 1 );
            for (int j = i; j <= n and b[j] == 0; j++) dp[j][1][1] = min(dp[j][1][1], min(dp[i-1][0][1], dp[i-1][1][1]) + 1 );
        }
        if (b[i] == 1) {
            for (int j = i; j <= n and b[j] == 1; j++) dp[j][1][0] = min(dp[j][1][0], min(dp[i-1][0][0], dp[i-1][1][0]) + 1 );
            for (int j = i; j <= n and b[j] == 1; j++) dp[j][1][1] = min(dp[j][1][1], min(dp[i-1][0][1], dp[i-1][1][1]) + 1 );
        }
        if (a[i] != b[i]) {
            for (int j = i; j <= n and b[j] != a[j]; j++) dp[j][1][1] = min(dp[j][1][1], min(dp[i-1][1][1], dp[i-1][1][0]+1));
            for (int j = i; j <= n and b[j] != a[j]; j++) dp[j][1][1] = min(dp[j][1][1], dp[i-1][0][0]+1);
        } 
    }

    int ans = INT_MAX;
    for (int i = 0; i < 2; i++) for (int j = 0; j < 2; j++) ans = min(ans, dp[n][i][j]);
    cout << ans << '\n';
}

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