Submission #115839

#	Time	Username	Problem	Language	Result	Execution time	Memory
115839		RockyB	Paint By Numbers (IOI16_paint)	C++17	100 / 100	701 ms	180892 KiB

paint

/// In The Name Of God

#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>

#define f first
#define s second

#define pb push_back
#define pp pop_back
#define mp make_pair

#define sz(x) (int)x.size()
#define sqr(x) ((x) * 1ll * (x))
#define all(x) x.begin(), x.end()

#define rep(i, l, r) for (int i = (l); i <= (r); i++)
#define Kazakhstan ios_base :: sync_with_stdio(0), cin.tie(0), cout.tie(0);

#define nl '\n'
#define ioi exit(0);

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;

const int N = (int)4e5 + 7;
const int inf = (int)1e9 + 7;
const int mod = (int)1e9 + 7;
const ll linf = (ll)1e18 + 7;

const int dx[] = {-1, 0, 1, 0, 1, -1, -1, 1};
const int dy[] = {0, 1, 0, -1, 1, -1, 1, -1};

using namespace std;

int n, k;
int pref[N];

vector <int> a;
string s;

int bad[N];

bool check(int l, int r) {
	return !(l ? pref[r] - pref[l - 1] : pref[r]) && (r + 1 == n || s[r + 1] != 'X');
}

int dp[N][105];

vector < pair <int, int> > rng;
string cur;

int X[N], _[N];
int calc(int v, int id) {
	if (v >= n) {
		return id == k;
	}
	if (~dp[v][id]) return dp[v][id];
	int res = 0;
	if (s[v] != 'X') {
        if (calc(v + 1, id)) {
            X[v]++;
            X[v + 1]--;
            res |= 1;
        }
	}
	if (id < k && v + a[id] <= n) {
		if (check(v, v + a[id] - 1) && calc(v + a[id] + 1, id + 1)) {
			_[v]++;
            _[v + a[id]]--;
            X[v + a[id]]++;
            X[v + a[id] + 1]--;
            res |= 1;
        }
	}
	return dp[v][id] = res;
}
string solve_puzzle(string S, vector <int> c) {
	n = sz(S);
	s = S;
	a = c;
	k = sz(c);
	// --- coppying

	for (int i = 0; i < n; i++) {
		pref[i] = s[i] == '_';
		if (i) pref[i] += pref[i - 1];
	}
	memset(dp, -1, sizeof(dp));
	calc(0, 0);
	for (int i = 1; i < n; i++) {
        X[i] += X[i - 1];
        _[i] += _[i - 1];
    }
	for (int i = 0; i < n; i++) {
		if (X[i] && _[i]) s[i] = '?';
        else if (X[i]) s[i] = '_';
        else s[i] = 'X';
	}
	return s;
}

#ifdef IOI2018

const int S_MAX_LEN = 200 * 1000;
char buf[S_MAX_LEN + 1];

int main() {
	freopen ("in.txt", "r", stdin);
	freopen ("D.out", "w", stdout);
    assert(1 == scanf("%s", buf));
    std::string s = buf;
    int c_len;
    assert(1 == scanf("%d", &c_len));
    std::vector<int> c(c_len);
    for (int i = 0; i < c_len; i++) {
        assert(1 == scanf("%d", &c[i]));
    }
    std::string ans = solve_puzzle(s, c);


    printf("%s\n", ans.data());
    return 0;
}

#endif

• Subtask 1: 7 / 7
• Subtask 2: 3 / 3
• Subtask 3: 22 / 22
• Subtask 4: 27 / 27
• Subtask 5: 21 / 21
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10