Submission #729729

#	Time	Username	Problem	Language	Result	Execution time	Memory
729729		_callmelucian	Lamps (JOI19_lamps)	C++14	4 / 100	89 ms	48380 KiB

lamp

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
#define NL "\n"
#define SP " "
#define fmax(a, b) a = max(a, b)
#define fmin(a, b) a = min(a, b)
#define all(v) v.begin(), v.end()

const int mn = 1e6 + 1;
ll dp[mn][2][3];
bool A[mn], B[mn];

ll cost1 (int a, int b) {
    if (b == 0 || a == b) return 0;
    return 1;
}

ll cost2 (int a, int b) {
    if (b == 2 || a == b) return 0;
    return 1;
}

void update (int i, int j, int k) {
    for (int j2 = 0; j2 < 2; j2++) {
        for (int k2 = 0; k2 < 3; k2++)
            dp[i][j][k] = min(dp[i][j][k], dp[i - 1][j2][k2] + cost1(j2, j) + cost2(k2, k));
    }
    return;
}

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);

    int n; cin >> n;
    for (int i = 1; i <= n; i++) {
        char c; cin >> c;
        if (c == '1') A[i] = 1;
    }
    for (int i = 1; i <= n; i++) {
        char c; cin >> c;
        if (c == '1') B[i] = 1;
    }

    for (int i = 0; i <= n; i++) {
        for (int j = 0; j < 2; j++) {
            for (int k = 0; k < 3; k++) dp[i][j][k] = INT_MAX;
        }
    }
    dp[0][0][2] = 0;
    for (int i = 1; i <= n; i++) {
        // xor
        if (A[i] != B[i]) {
            update(i, 1, 2);
            update(i, 1, B[i]);
        }
        else update(i, 1, B[i]);

        // not xor
        if (A[i] != B[i]) update(i, 0, B[i]);
        else {
            update(i, 0, 2);
            update(i, 0, B[i]);
        }
    }

    ll ans = LLONG_MAX;
    for (int j = 0; j < 2; j++) {
        for (int k = 0; k < 3; k++) ans = min(ans, dp[n][j][k]);
    }
    cout << ans;

    return 0;
}

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