oj.uz

Submission #456437

# Submission time Handle Problem Language Result Execution time Memory
456437 2021-08-06T17:39:05 Z dxz05 Bomb (IZhO17_bomb) C++14
49 / 100
 1000 ms 55972 KB 
#pragma GCC optimize("Ofast,O2,O3")
#pragma GCC target("avx2")

#include <bits/stdc++.h>

using namespace std;

void debug_out() { cerr << endl; }

template<typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
    cerr << "[" << H << "]";
    debug_out(T...);
}

#ifdef dddxxz
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

#define SZ(s) ((int)s.size())
#define all(x) (x).begin(), (x).end()
#define revall(x) (x).rbegin(), (x).rend()

clock_t startTime;

double getCurrentTime() {
    return (double) (clock() - startTime) / CLOCKS_PER_SEC;
}

#define MP make_pair

typedef long long ll;
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
const double eps = 0.00001;
const int MOD = 1e9;
const int INF = 1000000101;
const long long LLINF = 1223372000000000555;
const int N = 2e6 + 3e2;
const int M = 2522;

int n, m;
int a[M][M];
bool bomb[M][M];
int dp[M][M];

int sum(int x1, int y1, int x2, int y2){
    if (min({x1, y1, x2, y2}) < 1 || max(x1, x2) > n || max(y1, y2) > m) return -1;
    assert(x1 <= x2 && y1 <= y2);
    int res = dp[x2][y2];
    res -= dp[x1 - 1][y2];
    res -= dp[x2][y1 - 1];
    res += dp[x1 - 1][y1 - 1];
    return res;
}

int ans = 0;

bool fill(int x1, int y1, int x2, int y2){
    if (sum(x1, y1, x2, y2) != (x2 - x1 + 1) * (y2 - y1 + 1)) return false;
    for (int i = x1; i <= x2; i++){
        for (int j = y1; j <= y2; j++){
            bomb[i][j] = true;
        }
    }
    return true;
}

bool check(int A, int B){
    //if (ans > A * B) return true;

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++) bomb[i][j] = false;
    }

    for (int i = 1; i <= n - A + 1; i++){
        for (int j = 1; j <= m - B + 1; j++){
            if (!a[i][j] || bomb[i][j]) continue;
            fill(i, j, i + A - 1, j + B - 1);
        }
    }

    for (int i = n; i >= A; i--){
        for (int j = 1; j <= m - B + 1; j++){
            if (!a[i][j] || bomb[i][j]) continue;
            fill(i - A + 1, j, i, j + B - 1);
        }
    }

    for (int i = 1; i <= n - A + 1; i++){
        for (int j = m; j >= B; j--){
            if (!a[i][j] || bomb[i][j]) continue;
            fill(i, j - B + 1, i + A - 1, j);
        }
    }

    for (int i = n; i >= A; i--){
        for (int j = m; j >= B; j--){
            if (!a[i][j] || bomb[i][j]) continue;
            fill(i - A + 1, j - B + 1, i, j);
        }
    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (a[i][j] && !bomb[i][j]) return false;
        }
    }

    ans = max(ans, A * B);

    return true;
}

void solve(int TC) {
    cin >> n >> m;

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            char ch;
            cin >> ch;
            a[i][j] = ch - '0';
            dp[i][j] = dp[i][j - 1] + a[i][j];
        }
    }

    for (int j = 1; j <= m; j++){
        for (int i = 1; i <= n; i++){
            dp[i][j] += dp[i - 1][j];
        }
    }

    int A = n, B = m;
    for (int j = 1; j <= m; j++){
        for (int i = 1; i <= n; i++){
            if (a[i][j] == 0) continue;
            int k = i;
            while (k <= n && a[k][j] == 1) k++;
            A = min(A, k - i);
            i = k - 1;
        }
    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (a[i][j] == 0) continue;
            int k = j;
            while (k <= m && a[i][k] == 1) k++;
            B = min(B, k - j);
            j = k - 1;
        }
    }

    if (check(A, B)){
        cout << ans;
        return;
    }

    if (A < B){
        for (int i = 1; i <= A; i++){
            int l = 1, r = B;
            while (l <= r){
                int mid = (l + r) >> 1;
                if (check(i, mid)){
                    l = mid + 1;
                } else r = mid - 1;
            }
        }
    } else {
        for (int i = 1; i <= B; i++){
            int l = 1, r = A;
            while (l <= r){
                int mid = (l + r) >> 1;
                if (check(mid, i)){
                    l = mid + 1;
                } else r = mid - 1;
            }
        }
    }

    cout << ans;

}

int main() {
    startTime = clock();
    cin.tie(nullptr);
    cout.tie(nullptr);
    ios_base::sync_with_stdio(false);

    bool llololcal = false;
#ifdef dddxxz
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    llololcal = true;
#endif

    int TC = 1;
    //cin >> TC;

    for (int test = 1; test <= TC; test++) {
        debug(test);
        //cout << "Case #" << test << ": ";
        solve(test);
    }

    if (llololcal) cerr << endl << "Time: " << int(getCurrentTime() * 1000) << " ms" << endl;

    return 0;
}

Compilation message

bomb.cpp: In function 'int main()':
bomb.cpp:19:20: warning: statement has no effect [-Wunused-value]
   19 | #define debug(...) 42
      |                    ^~
bomb.cpp:203:9: note: in expansion of macro 'debug'
  203 |         debug(test);
      |         ^~~~~

Subtask #1
49.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Correct 14 ms 26496 KB Output is correct
4 Correct 14 ms 26572 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 460 KB Output is correct
9 Correct 1 ms 460 KB Output is correct
10 Correct 1 ms 388 KB Output is correct
11 Correct 1 ms 460 KB Output is correct
12 Correct 1 ms 460 KB Output is correct
13 Correct 1 ms 460 KB Output is correct
14 Correct 1 ms 460 KB Output is correct
15 Correct 1 ms 460 KB Output is correct
16 Correct 1 ms 460 KB Output is correct
17 Correct 1 ms 972 KB Output is correct
18 Correct 1 ms 1100 KB Output is correct
19 Correct 4 ms 1372 KB Output is correct
20 Correct 5 ms 1356 KB Output is correct
21 Correct 1 ms 844 KB Output is correct
22 Correct 2 ms 1100 KB Output is correct
23 Correct 8 ms 1356 KB Output is correct
24 Correct 4 ms 1228 KB Output is correct
25 Correct 12 ms 1460 KB Output is correct
26 Correct 1 ms 1356 KB Output is correct
27 Correct 4 ms 4044 KB Output is correct
28 Correct 17 ms 4244 KB Output is correct
29 Correct 478 ms 5384 KB Output is correct
30 Correct 698 ms 6316 KB Output is correct
31 Correct 400 ms 4940 KB Output is correct
32 Correct 329 ms 5816 KB Output is correct
33 Execution timed out 1078 ms 6624 KB Time limit exceeded
34 Correct 19 ms 4684 KB Output is correct
35 Correct 131 ms 6604 KB Output is correct
36 Correct 8 ms 6588 KB Output is correct
37 Correct 1 ms 460 KB Output is correct
38 Correct 188 ms 55748 KB Output is correct
39 Correct 1 ms 460 KB Output is correct
40 Execution timed out 1075 ms 15440 KB Time limit exceeded
41 Correct 1 ms 460 KB Output is correct
42 Correct 17 ms 1456 KB Output is correct
43 Correct 298 ms 55840 KB Output is correct
44 Execution timed out 1088 ms 6604 KB Time limit exceeded
45 Execution timed out 1092 ms 55724 KB Time limit exceeded
46 Correct 272 ms 55796 KB Output is correct
47 Execution timed out 1092 ms 55728 KB Time limit exceeded
48 Execution timed out 1100 ms 55752 KB Time limit exceeded
49 Correct 237 ms 55972 KB Output is correct
50 Execution timed out 1094 ms 55780 KB Time limit exceeded
51 Execution timed out 1092 ms 55748 KB Time limit exceeded
52 Execution timed out 1089 ms 55748 KB Time limit exceeded
53 Execution timed out 1092 ms 55904 KB Time limit exceeded
54 Execution timed out 1085 ms 55876 KB Time limit exceeded
55 Execution timed out 1093 ms 55752 KB Time limit exceeded
56 Correct 197 ms 55788 KB Output is correct
57 Execution timed out 1084 ms 55824 KB Time limit exceeded
58 Execution timed out 1043 ms 55816 KB Time limit exceeded
59 Execution timed out 1042 ms 55748 KB Time limit exceeded
60 Correct 226 ms 55848 KB Output is correct
61 Correct 230 ms 55816 KB Output is correct
62 Correct 229 ms 55848 KB Output is correct
63 Correct 202 ms 55744 KB Output is correct
64 Correct 224 ms 55748 KB Output is correct
65 Execution timed out 1077 ms 55756 KB Time limit exceeded
66 Execution timed out 1084 ms 55748 KB Time limit exceeded
67 Execution timed out 1097 ms 55768 KB Time limit exceeded
68 Execution timed out 1092 ms 55816 KB Time limit exceeded
69 Execution timed out 1095 ms 55780 KB Time limit exceeded
70 Execution timed out 1088 ms 44612 KB Time limit exceeded
71 Execution timed out 1092 ms 55720 KB Time limit exceeded
72 Execution timed out 1080 ms 55796 KB Time limit exceeded
73 Execution timed out 1088 ms 55740 KB Time limit exceeded
74 Execution timed out 1090 ms 55804 KB Time limit exceeded
75 Execution timed out 1093 ms 55716 KB Time limit exceeded
76 Execution timed out 1059 ms 55876 KB Time limit exceeded
77 Execution timed out 1095 ms 55748 KB Time limit exceeded
78 Execution timed out 1082 ms 55748 KB Time limit exceeded
79 Execution timed out 1057 ms 55724 KB Time limit exceeded
80 Execution timed out 1088 ms 55748 KB Time limit exceeded
81 Execution timed out 1087 ms 55848 KB Time limit exceeded
82 Execution timed out 1080 ms 55812 KB Time limit exceeded
83 Execution timed out 1097 ms 55788 KB Time limit exceeded
84 Execution timed out 1035 ms 55740 KB Time limit exceeded
85 Execution timed out 1093 ms 55796 KB Time limit exceeded
86 Execution timed out 1085 ms 55724 KB Time limit exceeded
87 Execution timed out 1093 ms 55832 KB Time limit exceeded
88 Execution timed out 1086 ms 55744 KB Time limit exceeded
89 Execution timed out 1091 ms 55748 KB Time limit exceeded
90 Execution timed out 1090 ms 44716 KB Time limit exceeded
91 Execution timed out 1096 ms 55816 KB Time limit exceeded
92 Execution timed out 1089 ms 55796 KB Time limit exceeded
93 Execution timed out 1100 ms 55748 KB Time limit exceeded
94 Execution timed out 1094 ms 55792 KB Time limit exceeded
95 Execution timed out 1085 ms 55780 KB Time limit exceeded
96 Execution timed out 1092 ms 55820 KB Time limit exceeded
97 Execution timed out 1100 ms 55808 KB Time limit exceeded
98 Execution timed out 1057 ms 55812 KB Time limit exceeded
99 Execution timed out 1089 ms 55744 KB Time limit exceeded
100 Execution timed out 1095 ms 55740 KB Time limit exceeded