Submission #422378

#	Time	Username	Problem	Language	Result	Execution time	Memory
422378		qwerasdfzxcl	Lamps (JOI19_lamps)	C++14	4 / 100	27 ms	20032 KiB

lamp

#include <bits/stdc++.h>

typedef long long ll;
using namespace std;
string x, y;
int dp[1001000][3], ans[1001000];

int main(){
    cin.tie(NULL);
    ios_base::sync_with_stdio(false);
    int n;
    cin >> n >> x >> y;
    if (x[0]==y[0]){
        if (y[0]=='0') dp[0][0] = 1, dp[0][1] = 2;
        else dp[0][0] = 2, dp[0][1] = 1;
        dp[0][2] = 2;
    }
    else{
        if (y[0]=='0') dp[0][0] = 1, dp[0][1] = 2;
        else dp[0][0] = 2, dp[0][1] = 1;
        dp[0][2] = 1;
        ans[0] = 1;
    }
    for (int i=1;i<n;i++){
        if (y[i]==y[i-1]) dp[i][0] = dp[i-1][0], dp[i][1] = dp[i-1][1];
        else dp[i][y[i]-'0'] = dp[i-1][y[i]-'0'], dp[i][(y[i]-'0')^1] = dp[i-1][(y[i]-'0')^1]+1;
        if (x[i]!=y[i]){
            dp[i][2] = min(dp[i-1][2], ans[i-1]+1);
            ans[i] = min(ans[i-1]+1, min(dp[i][0], min(dp[i][1], dp[i][2])));
        }
        else{
            dp[i][2] = min(ans[i-1]+2, min(dp[i-1][2], dp[i-1][(y[i]-'0')^1])+1);
            ans[i] = ans[i-1];
        }
    }
    /*for (int i=0;i<n;i++) printf("%d", dp[i][0]);
    printf("\n");
    for (int i=0;i<n;i++) printf("%d", dp[i][1]);
    printf("\n");
    for (int i=0;i<n;i++) printf("%d", dp[i][2]);
    printf("\n");
    for (int i=0;i<n;i++) printf("%d", ans[i]);
    printf("\n");*/
    cout << ans[n-1];
    return 0;
}

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