Submission #65961

#	Time	Username	Problem	Language	Result	Execution time	Memory
65961		gs13068	Paint By Numbers (IOI16_paint)	C++17	100 / 100	223 ms	54180 KiB

paint

#include "paint.h"
#include <cstdio>
#include <cstdlib>
 
int a[200002];
bool L[200002][111];
bool R[200002][111];
int yes[200002], no[200002];
 
std::string solve_puzzle(std::string s, std::vector<int> c) {
    int i, j;
    int n = s.size(), m = c.size();
    for (i = 0; i < n; i++) a[i + 1] = a[i] + (s[i] == '_');
    L[0][0] = true;
    for (i = 1; i <= n; i++) for (j = 0; j <= m; j++) {
        if (s[i - 1] != 'X' && L[i - 1][j]) {
            L[i][j] = true;
            continue;
        }
        if (j && i >= c[j - 1] && a[i] == a[i - c[j - 1]] && (j == 1 ? L[i - c[0]][0] : i > c[j - 1] && L[i - c[j - 1] - 1][j - 1] && s[i - c[j - 1] - 1] != 'X')) L[i][j] = true;
    }
    R[n + 1][m] = true;
    for (i = n; i >= 1; i--) for (j = m; j >= 0; j--) {
        if (j < m && i + c[j] <= n + 1 && a[i - 1] == a[i + c[j] - 1] && (j + 1 == m ? R[i + c[j]][j + 1] : i + c[j] < n + 1 && R[i + c[j] + 1][j + 1] && s[i + c[j] - 1] != 'X')) {
            R[i][j] = true;
            if (j ? i > 1 && L[i - 2][j] && s[i - 2] != 'X' : L[i - 1][0]) {
                yes[i - 1]++;
                yes[i + c[j] - 1]--;
            }
            continue;
        }
        if (s[i - 1] != 'X' && R[i + 1][j]) R[i][j] = true;
    }
//  for (j = 0; j <= m; j++, puts("")) for (i = 0; i <= n + 1; i++) printf("%d ", L[i][j]); puts("");
//  for (j = 0; j <= m; j++, puts("")) for (i = 0; i <= n + 1; i++) printf("%d ", R[i][j]); puts("");
    std::string res;
    for (i = 0; i < n; i++) {
        yes[i + 1] += yes[i];
        if (s[i] != 'X') {
            for (j = 0; j <= m; j++) if (L[i][j] && R[i + 2][j]) break;
            no[i] = j <= m;
        }
        res.push_back(yes[i] && no[i] ? '?' : yes[i] ? 'X' : '_');
    }
    return res;
}

• 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