Submission #643085

#	Time	Username	Problem	Language	Result	Execution time	Memory
643085		ddy888	Paint By Numbers (IOI16_paint)	C++17	32 / 100	0 ms	212 KiB

paint

// #include "paint.h"
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#pragma GCC optimize("unroll-loops")
using namespace std;
using namespace __gnu_pbds;

using ll = long long;
#define pb push_back
#define fi first
#define si second
#define ar array
typedef pair<int,int> pi;
typedef tuple<int,int,int> ti;  
template<typename T> bool chmin(T &a, T b){return (b < a) ? a = b, 1 : 0;}
template<typename T> bool chmax(T &a, T b){return (b > a) ? a = b, 1 : 0;}
template<class key, class value = null_type, class cmp = less<key> >
using ordered_set = tree<key, value, cmp, rb_tree_tag, tree_order_statistics_node_update>;
mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

void debug_out() {cerr<<endl;}
template <typename Head, typename... Tail>
void debug_out(Head _H, Tail... _T) {cerr<<" "<<to_string(_H);debug_out(_T...);}
#define debug(...) cerr<<"["<<#__VA_ARGS__<<"]:",debug_out(__VA_ARGS__)
const int MAXN = 200010;

int n, m;
int arr[MAXN], lo[MAXN], hi[MAXN]; // left endpoint
vector<int> wc, bc;

string solve_puzzle(std::string s, std::vector<int> c) {
    n = s.size();
    m = c.size();
    for (int i = 1; i <= m; ++i) arr[i] = c[i-1];
    for (int i = 1; i <= n; ++i) {
        if (s[i-1] == 'X') bc.pb(i);
        else if (s[i-1] == '_') wc.pb(i);
    }
    vector<int> ori = wc;
    
    int ptr = 1;
    for (int i = 1; i <= m; ++i) {
        while (1) {
            auto near = lower_bound(wc.begin(), wc.end(), ptr);
            if (near != wc.end()) {
                if (*near <= ptr + arr[i] - 1) {
                    ptr = *near + 1;
                }
            }
            lo[i] = ptr;
            break;
        }
        ptr += arr[i] + 1;
    }

    ptr = n - arr[m] + 1;
    for (int i = m; i >= 1; --i) {
        while (1) {
            auto near = lower_bound(wc.begin(), wc.end(), ptr);
            if (near != wc.end()) {
                if (*near <= ptr + arr[i] - 1) {
                    ptr = *(--near);
                }
            }
            hi[i] = ptr;
            break;
        }
        ptr -= arr[i-1]; --ptr;
    }
    // for (int i = 1; i <= m; ++i) debug(lo[i], hi[i]);
    vector<pi> black, white;
    for (int i = 1; i <= m; ++i) {
        if (lo[i] == hi[i]) {
            black.pb({lo[i], lo[i]+arr[i]-1});
            white.pb({lo[i]+arr[i], lo[i]+arr[i]});
        } else {
            if (hi[i] <= lo[i] + arr[i] - 1) {
                black.pb({hi[i], lo[i] + arr[i] - 1});
            }
        }
    }   
    string ans = "";
    for (int i = 0; i < n; ++i) ans += '?';
    for (auto [l,r]: black) {
        for (int idx = l; idx <= r; ++ idx) if (idx <= n) ans[idx-1] = 'X';
    }
    for (auto [l,r]: white) {
        for (int idx = l; idx <= r; ++ idx) if (idx <= n) ans[idx-1] = '_';   
    }
    for (int i = 0; i < n; ++i) if (ans[i] == '?' && s[i] != '.') ans[i] = s[i];
    return ans;
}

• Subtask 1: 7 / 7
• Subtask 2: 3 / 3
• Subtask 3: 22 / 22
• Subtask 4: 0 / 27
• Subtask 5: 0 / 21
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10