Submission #1092960

#	Time	Username	Problem	Language	Result	Execution time	Memory
1092960		anhthi	Lamps (JOI19_lamps)	C++14	100 / 100	224 ms	67228 KiB

lamp

#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define ll long long
#define mp(x, y) make_pair(x, y)
#define sz(v) ((int) (v).size())
#define all(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define BIT(x, y) (((x) >> (y)) & 1)
#define pb push_back
#define max_rng *max_element
#define min_rng *min_element
#define rep(i, n) for(int i = 1, _n = (n); i <= _n; ++i)
#define forn(i, a, b) for(int i = (a), _b = (b); i <= _b; ++i)
#define ford(i, a, b) for(int i = (a), _b = (b); i >= _b; --i)

template <class X, class Y>
    inline bool maximize(X &x, Y y) {
        return (x < y ? x = y, true : false);
    }

template <class X, class Y>
    inline bool minimize(X &x, Y y) {
        return (x > y ? x = y, true : false);
    }

template <class X>
    inline void compress(vector<X> &a) {
        sort(all(a));
        a.resize(unique(all(a)) - a.begin());
    }

int ctz(ll x) { return __builtin_ctzll(x); }
int lg(ll x) { return 63 - __builtin_clzll(x); }
int popcount(ll x) { return __builtin_popcount(x); }

mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) {
    return l + abs((ll) rng()) % (r - l + 1);
}

const ll oo = (ll) 1e17;
const int inf = (int) 1e9, mod = (int) 1e9 + 7;

const int mxn = 1e6 + 5, mxm = 2e2 + 5, base = 307, LOG = 20;

void add(int &x, int y) { x += y; if (x >= mod) x -= mod; }
void sub(int &x, int y) { x -= y; if (x < 0) x += mod; }

int n;
string A, B;

vector<vector<int>> op;

int trans[16][2];
int f[16][16], g[10][10];

int dp[mxn][16];

void prepare() {
    vector<int> p(3);
    iota(all(p), 0);

    do {
        vector<int> cur;
        for (int v : p) {
            cur.pb(v);
            op.pb(cur);
        }
    } while (next_permutation(all(p)));

    op.pb(vector<int>());

    compress(op);

    memset(f, 0x3f, sizeof f);
    forn(i, 0, sz(op) - 1) forn(j, 0, sz(op) - 1) {
        const vector<int> &a = op[i];
        const vector<int> &b = op[j];

        forn(x, 1, sz(a)) forn(y, 1, sz(b)) {
            g[x][y] = max(g[x][y-1], g[x-1][y]);
            if (a[x - 1] == b[y - 1])
                maximize(g[x][y], g[x - 1][y - 1] + 1);
        }
        f[i][j] = sz(b) - g[sz(a)][sz(b)];
    }

    forn(i, 0, sz(op) - 1) forn(j, 0, 1) {
        int bit = j;
        for (int o : op[i]) {
            if (!o) bit = 0;
            else if (o == 1) bit = 1;
            else bit ^= 1;
        }
        trans[i][j] = bit;
    }

    return;
}

int main(void) {
    // think what before starting to code
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    #define TASK "partner"
    if (fopen(TASK".inp", "r")) {
        freopen(TASK".inp", "r", stdin);
        freopen(TASK".out", "w", stdout);
    }

    cin >> n >> A >> B;

    prepare();

    memset(dp, 0x3f, sizeof dp);

    dp[0][0] = 0;
    rep(i, n) {
        int d1 = A[i-1] - '0', d2 = B[i-1] - '0';
        forn(cur, 0, 15) if (trans[cur][d1] == d2) {
            forn(pre, 0, 15) {
                minimize(dp[i][cur], dp[i - 1][pre] + f[pre][cur]);
            }
        }
    }

    cout << min_rng(dp[n], dp[n] + 16);

    return 0;
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:112:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  112 |         freopen(TASK".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
lamp.cpp:113:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |         freopen(TASK".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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