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  1. // ~~ icebear ~~
  2. #include <bits/stdc++.h>
  3. using namespace std;
  4.  
  5. typedef long long ll;
  6. typedef pair<int, int> ii;
  7. typedef pair<int, ii> iii;
  8.  
  9. template<class T>
  10. bool minimize(T &a, const T &b) {
  11. if (a > b) return a = b, true;
  12. return false;
  13. }
  14.  
  15. template<class T>
  16. bool maximize(T &a, const T &b) {
  17. if (a < b) return a = b, true;
  18. return false;
  19. }
  20.  
  21. #define FOR(i,a,b) for(int i=(a); i<=(b); ++i)
  22. #define FORR(i,a,b) for(int i=(a); i>=(b); --i)
  23. #define REP(i, n) for(int i=0; i<(n); ++i)
  24. #define RED(i, n) for(int i=(n)-1; i>=0; --i)
  25. #define MASK(i) (1LL << (i))
  26. #define BIT(S, i) (((S) >> (i)) & 1)
  27. #define mp make_pair
  28. #define pb push_back
  29. #define fi first
  30. #define se second
  31. #define all(x) x.begin(), x.end()
  32. #define task "icebear"
  33.  
  34. const int MOD = 1e9 + 7;
  35. const int inf = 1e9 + 27092008;
  36. const ll INF = 1e18 + 27092008;
  37. const int N = 2000 + 5;
  38. int n, m, pref[N][N];
  39. char a[N][N];
  40. map<int, bool> M[N][N];
  41. int ans;
  42.  
  43. void expandTop(int x, int y) {
  44. int dis = 1, i = x;
  45. while(i <= n) {
  46. if (y - dis < 1 || y + dis > m) break;
  47. if (pref[i][y + dis - 1] - pref[i][y - dis] > 0 || a[i][y - dis] != '#' || a[i][y + dis] != '#') break;
  48. M[i][y][dis] = true;
  49. i++; dis++;
  50. }
  51. }
  52.  
  53. void expandBot(int x, int y) {
  54. int dis = 1, i = x;
  55. while(i >= 1) {
  56. if (y - dis < 1 || y + dis > m) break;
  57. if (pref[i][y + dis - 1] - pref[i][y - dis] > 0 || a[i][y - dis] != '#' || a[i][y + dis] != '#') break;
  58. if (M[i][y].find(dis) != M[i][y].end()) ans++;
  59. i--; dis++;
  60. }
  61. }
  62.  
  63. void init(void) {
  64. cin >> n >> m;
  65. FOR(i, 1, n) {
  66. FOR(j, 1, m) cin >> a[i][j];
  67. FOR(j, 1, m) pref[i][j] = pref[i][j - 1] + (a[i][j] == '#');
  68. }
  69. }
  70.  
  71. void process(void) {
  72. FOR(i, 2, n - 1) FOR(j, 2, m - 1) {
  73. if (a[i - 1][j] == '#' && a[i][j - 1] == '#' && a[i][j + 1] == '#' && a[i][j] == '.')
  74. expandTop(i, j);
  75. if (a[i + 1][j] == '#' && a[i][j - 1] == '#' && a[i][j + 1] == '#' && a[i][j] == '.')
  76. expandBot(i, j);
  77. }
  78. cout << ans;
  79. }
  80.  
  81. int main() {
  82. ios_base::sync_with_stdio(0);
  83. cin.tie(0); cout.tie(0);
  84. if (fopen(task".inp", "r")) {
  85. freopen(task".inp", "r", stdin);
  86. freopen(task".out", "w", stdout);
  87. }
  88. int tc = 1;
  89. // cin >> tc;
  90. while(tc--) {
  91. init();
  92. process();
  93. }
  94. return 0;
  95. }
Success #stdin #stdout 0.05s 193196KB
stdin
Standard input is empty
stdout
Standard output is empty