oj.uz

Submission #456261

# Submission time Handle Problem Language Result Execution time Memory
456261 2021-08-06T09:54:53 Z dxz05 Bomb (IZhO17_bomb) C++14
45 / 100
 1000 ms 62144 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){
    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 check(int A, int B){
    if (A * B < ans) 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]) continue;
            if (sum(i, j, i + A - 1, j + B - 1) == A * B){
                for (int x = i; x <= i + A - 1; x++){
                    for (int y = j; y <= j + B - 1; y++){
                        bomb[x][y] = true;
                    }
                }
            }
        }
    }

//    for (int i = n; i >= A; i--){
//        for (int j = m; j >= B; j--){
//            if (!a[i][j]) continue;
//            if (sum(i - A + 1, j - B + 1, i, j) == A * B){
//                for (int x = i - A + 1; x <= i; x++){
//                    for (int y = j - B + 1; y <= j; y++){
//                        bomb[x][y] = true;
//                    }
//                }
//            }
//        }
//    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (!bomb[i][j] && a[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 (n < m){
        for (int i = 1; i <= n; i++){
            int l = 1, r = m;
            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 <= m; i++){
            int l = 1, r = n;
            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:189:9: note: in expansion of macro 'debug'
  189 |         debug(test);
      |         ^~~~~

Subtask #1
45.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Correct 14 ms 26572 KB Output is correct
4 Correct 15 ms 26572 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 324 KB Output is 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 Correct 3 ms 972 KB Output is correct
18 Correct 3 ms 1100 KB Output is correct
19 Correct 8 ms 1384 KB Output is correct
20 Correct 6 ms 1356 KB Output is correct
21 Correct 2 ms 844 KB Output is correct
22 Correct 4 ms 1100 KB Output is correct
23 Correct 10 ms 1356 KB Output is correct
24 Correct 5 ms 1228 KB Output is correct
25 Correct 16 ms 1356 KB Output is correct
26 Correct 2 ms 1356 KB Output is correct
27 Correct 4 ms 4044 KB Output is correct
28 Correct 212 ms 4332 KB Output is correct
29 Execution timed out 1082 ms 5452 KB Time limit exceeded
30 Execution timed out 1078 ms 6476 KB Time limit exceeded
31 Correct 904 ms 5144 KB Output is correct
32 Correct 749 ms 5964 KB Output is correct
33 Execution timed out 1086 ms 6732 KB Time limit exceeded
34 Correct 138 ms 4768 KB Output is correct
35 Correct 751 ms 6820 KB Output is correct
36 Correct 44 ms 6732 KB Output is correct
37 Correct 1 ms 460 KB Output is correct
38 Correct 192 ms 61892 KB Output is correct
39 Correct 1 ms 460 KB Output is correct
40 Execution timed out 1085 ms 16180 KB Time limit exceeded
41 Correct 1 ms 460 KB Output is correct
42 Correct 48 ms 1448 KB Output is correct
43 Execution timed out 1086 ms 61888 KB Time limit exceeded
44 Execution timed out 1085 ms 6732 KB Time limit exceeded
45 Execution timed out 1095 ms 61892 KB Time limit exceeded
46 Correct 226 ms 61924 KB Output is correct
47 Execution timed out 1086 ms 61948 KB Time limit exceeded
48 Execution timed out 1087 ms 61892 KB Time limit exceeded
49 Correct 409 ms 61952 KB Output is correct
50 Execution timed out 1093 ms 61852 KB Time limit exceeded
51 Execution timed out 1092 ms 61856 KB Time limit exceeded
52 Execution timed out 1095 ms 61932 KB Time limit exceeded
53 Execution timed out 1093 ms 61876 KB Time limit exceeded
54 Execution timed out 1093 ms 61900 KB Time limit exceeded
55 Execution timed out 1090 ms 61924 KB Time limit exceeded
56 Correct 198 ms 61852 KB Output is correct
57 Execution timed out 1100 ms 61912 KB Time limit exceeded
58 Execution timed out 1081 ms 61920 KB Time limit exceeded
59 Execution timed out 1084 ms 61932 KB Time limit exceeded
60 Correct 624 ms 61868 KB Output is correct
61 Correct 481 ms 61952 KB Output is correct
62 Execution timed out 1091 ms 61892 KB Time limit exceeded
63 Correct 900 ms 61888 KB Output is correct
64 Correct 278 ms 61920 KB Output is correct
65 Execution timed out 1093 ms 61848 KB Time limit exceeded
66 Execution timed out 1101 ms 61904 KB Time limit exceeded
67 Execution timed out 1099 ms 61896 KB Time limit exceeded
68 Execution timed out 1091 ms 61968 KB Time limit exceeded
69 Execution timed out 1083 ms 61892 KB Time limit exceeded
70 Execution timed out 1090 ms 48576 KB Time limit exceeded
71 Execution timed out 1082 ms 61852 KB Time limit exceeded
72 Execution timed out 1083 ms 61848 KB Time limit exceeded
73 Execution timed out 1090 ms 61920 KB Time limit exceeded
74 Execution timed out 1095 ms 61892 KB Time limit exceeded
75 Execution timed out 1081 ms 61888 KB Time limit exceeded
76 Execution timed out 1095 ms 61884 KB Time limit exceeded
77 Execution timed out 1085 ms 61892 KB Time limit exceeded
78 Execution timed out 1095 ms 61928 KB Time limit exceeded
79 Execution timed out 1097 ms 61892 KB Time limit exceeded
80 Execution timed out 1093 ms 61844 KB Time limit exceeded
81 Execution timed out 1093 ms 61892 KB Time limit exceeded
82 Execution timed out 1095 ms 61832 KB Time limit exceeded
83 Execution timed out 1099 ms 61868 KB Time limit exceeded
84 Execution timed out 1092 ms 62048 KB Time limit exceeded
85 Execution timed out 1096 ms 61924 KB Time limit exceeded
86 Execution timed out 1095 ms 61892 KB Time limit exceeded
87 Execution timed out 1051 ms 61892 KB Time limit exceeded
88 Execution timed out 1094 ms 61940 KB Time limit exceeded
89 Execution timed out 1093 ms 61932 KB Time limit exceeded
90 Execution timed out 1087 ms 48572 KB Time limit exceeded
91 Execution timed out 1091 ms 61916 KB Time limit exceeded
92 Execution timed out 1089 ms 61896 KB Time limit exceeded
93 Execution timed out 1085 ms 62144 KB Time limit exceeded
94 Execution timed out 1094 ms 62064 KB Time limit exceeded
95 Execution timed out 1100 ms 61928 KB Time limit exceeded
96 Execution timed out 1090 ms 61908 KB Time limit exceeded
97 Execution timed out 1090 ms 61884 KB Time limit exceeded
98 Execution timed out 1085 ms 62024 KB Time limit exceeded
99 Execution timed out 1097 ms 61924 KB Time limit exceeded
100 Execution timed out 1096 ms 61892 KB Time limit exceeded