Submission #456315

# Submission time Handle Problem Language Result Execution time Memory
456315 2021-08-06T11:53:41 Z dxz05 Bomb (IZhO17_bomb) C++14
43 / 100
1000 ms 55996 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, y1, x2, y2}) > n) 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 = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (!a[i][j] || bomb[i][j]) continue;
            if (fill(i, j, i + A - 1, j + B - 1)) continue;
            if (fill(i - A + 1, j, i, j + B - 1)) continue;
            if (fill(i, j - B + 1, i + A - 1, j)) continue;
            if (fill(i - A + 1, j - B + 1, i, j)) continue;
            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:187:9: note: in expansion of macro 'debug'
  187 |         debug(test);
      |         ^~~~~
# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 332 KB Output isn't correct
2 Correct 1 ms 460 KB Output is correct
3 Correct 13 ms 26524 KB Output is correct
4 Correct 15 ms 26516 KB Output is correct
5 Incorrect 1 ms 332 KB Output isn't correct
6 Incorrect 0 ms 332 KB Output isn't correct
7 Correct 1 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 460 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 Incorrect 1 ms 972 KB Output isn't correct
18 Correct 1 ms 1100 KB Output is correct
19 Incorrect 2 ms 1356 KB Output isn't correct
20 Correct 2 ms 1356 KB Output is correct
21 Correct 1 ms 844 KB Output is correct
22 Correct 1 ms 1100 KB Output is correct
23 Correct 5 ms 1480 KB Output is correct
24 Correct 2 ms 1228 KB Output is correct
25 Correct 7 ms 1356 KB Output is correct
26 Correct 1 ms 1356 KB Output is correct
27 Correct 4 ms 4044 KB Output is correct
28 Correct 10 ms 4172 KB Output is correct
29 Correct 301 ms 5396 KB Output is correct
30 Correct 260 ms 6216 KB Output is correct
31 Correct 157 ms 4940 KB Output is correct
32 Correct 122 ms 5708 KB Output is correct
33 Correct 503 ms 6624 KB Output is correct
34 Correct 10 ms 4704 KB Output is correct
35 Correct 36 ms 6604 KB Output is correct
36 Correct 8 ms 6640 KB Output is correct
37 Correct 1 ms 460 KB Output is correct
38 Correct 202 ms 55776 KB Output is correct
39 Correct 1 ms 460 KB Output is correct
40 Execution timed out 1084 ms 15436 KB Time limit exceeded
41 Incorrect 1 ms 460 KB Output isn't correct
42 Correct 11 ms 1484 KB Output is correct
43 Correct 512 ms 55844 KB Output is correct
44 Execution timed out 1079 ms 6556 KB Time limit exceeded
45 Execution timed out 1061 ms 55812 KB Time limit exceeded
46 Correct 211 ms 55844 KB Output is correct
47 Execution timed out 1093 ms 55856 KB Time limit exceeded
48 Execution timed out 1096 ms 55752 KB Time limit exceeded
49 Correct 228 ms 55796 KB Output is correct
50 Execution timed out 1093 ms 55748 KB Time limit exceeded
51 Execution timed out 1074 ms 55748 KB Time limit exceeded
52 Execution timed out 1091 ms 55776 KB Time limit exceeded
53 Execution timed out 1088 ms 55748 KB Time limit exceeded
54 Execution timed out 1088 ms 55876 KB Time limit exceeded
55 Execution timed out 1082 ms 55808 KB Time limit exceeded
56 Correct 212 ms 55876 KB Output is correct
57 Execution timed out 1095 ms 55808 KB Time limit exceeded
58 Execution timed out 1094 ms 55772 KB Time limit exceeded
59 Execution timed out 1088 ms 55748 KB Time limit exceeded
60 Correct 212 ms 55876 KB Output is correct
61 Execution timed out 1084 ms 55808 KB Time limit exceeded
62 Correct 237 ms 55772 KB Output is correct
63 Correct 213 ms 55824 KB Output is correct
64 Correct 212 ms 55748 KB Output is correct
65 Execution timed out 1090 ms 55784 KB Time limit exceeded
66 Execution timed out 1082 ms 55716 KB Time limit exceeded
67 Execution timed out 1053 ms 55820 KB Time limit exceeded
68 Execution timed out 1083 ms 55748 KB Time limit exceeded
69 Execution timed out 1092 ms 55768 KB Time limit exceeded
70 Execution timed out 1093 ms 44684 KB Time limit exceeded
71 Execution timed out 1084 ms 55820 KB Time limit exceeded
72 Execution timed out 1066 ms 55808 KB Time limit exceeded
73 Execution timed out 1095 ms 55816 KB Time limit exceeded
74 Execution timed out 1099 ms 55736 KB Time limit exceeded
75 Execution timed out 1082 ms 55752 KB Time limit exceeded
76 Execution timed out 1094 ms 55864 KB Time limit exceeded
77 Execution timed out 1086 ms 55748 KB Time limit exceeded
78 Execution timed out 1084 ms 55808 KB Time limit exceeded
79 Execution timed out 1091 ms 55736 KB Time limit exceeded
80 Execution timed out 1088 ms 55812 KB Time limit exceeded
81 Execution timed out 1086 ms 55876 KB Time limit exceeded
82 Execution timed out 1090 ms 55812 KB Time limit exceeded
83 Execution timed out 1024 ms 55816 KB Time limit exceeded
84 Execution timed out 1081 ms 55816 KB Time limit exceeded
85 Execution timed out 1058 ms 55740 KB Time limit exceeded
86 Execution timed out 1076 ms 55720 KB Time limit exceeded
87 Execution timed out 1051 ms 55736 KB Time limit exceeded
88 Execution timed out 1099 ms 55852 KB Time limit exceeded
89 Execution timed out 1073 ms 55996 KB Time limit exceeded
90 Execution timed out 1085 ms 44612 KB Time limit exceeded
91 Execution timed out 1095 ms 55808 KB Time limit exceeded
92 Execution timed out 1091 ms 55744 KB Time limit exceeded
93 Execution timed out 1078 ms 55744 KB Time limit exceeded
94 Execution timed out 1087 ms 55748 KB Time limit exceeded
95 Execution timed out 1097 ms 55812 KB Time limit exceeded
96 Execution timed out 1097 ms 55748 KB Time limit exceeded
97 Execution timed out 1087 ms 55812 KB Time limit exceeded
98 Execution timed out 1097 ms 55748 KB Time limit exceeded
99 Execution timed out 1075 ms 55808 KB Time limit exceeded
100 Execution timed out 1086 ms 55748 KB Time limit exceeded