Bzoj1619/p2919 [usaco 08nov] guardian farm guarding the farm

P2919 [usaco 08nov] Guard farm guarding the farm

Similar questions: p3456 [poi2007] grz-ridges and valleys

Each time the BFS is at the same altitude, it determines whether it is a hill based on the size of the surrounding blocks.

1 # include <iostream> 2 # include <cstdio> 3 # include <cstring> 4 # include <queue> 5 # include <cctype> 6 # define re register 7 using namespace STD; 8 void read (Int & X) {9 char c = getchar (); X = 0; 10 while (! Isdigit (c) c = getchar (); 11 while (isdigit (c) x = (x <3) + (x <1) + (C ^ 48), c = getchar (); 12} 13 # define n 70214 const int D1 [8] = {, 0,-, 1,-1, -1}; 15 const int D2 [8] = {,-, 1,-,-1}; 16 struct data {int X, Y ;}; 17 int n, m, H [N] [N], ans; bool vis [N] [N]; 18 void BFS (INT F1, int F2) {19 queue <DATA> H; H. push (data) {F1, F2}); 20 vis [F1] [F2] = 1; int p = 1; 21 While (! H. empty () {22 data u = H. front (); H. pop (); 23 for (INT I = 0; I <8; ++ I) {24 int R1 = u. X + D1 [I], R2 = u. Y + D2 [I]; 25 if (R1 <1 | R1> N | R2 <1 | r2> m) continue; 26 P & = (H [R1] [R2] <= H [U. x] [U. y]); // whether it is Hill 27 if (vis [R1] [R2]) continue; 28 If (H [R1] [R2] = H [U. x] [U. y]) 29 H. push (data) {R1, R2}), vis [R1] [R2] = 1; 30} 31} ans + = P; 32} 33 int main () {34 read (n); read (m); 35 for (Re int I = 1; I <= N; ++ I) 36 for (Re Int J = 1; j <= m; ++ J) 37 read (H [I] [J]); 38 for (R E int I = 1; I <= N; ++ I) 39 for (Re Int J = 1; j <= m; ++ J) 40 if (! Vis [I] [J]) BFS (I, j); 41 printf ("% d", ANS); 42 return 0; 43}

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Bzoj1619/p2919 [usaco 08nov] guardian farm guarding the farm