#include #include #include #define MAXR 40#define MAXC 40struct STACK{int x;int y;}stk[MAXR*MAXC];int stk_N=0;

void push(int x,int y){stk[stk_N].x=x;stk[stk_N].y=y;stk_N++;}void pop(int *x,int *y){stk_N--;*x=stk[stk_N].x;*y=stk[stk_N].y;}struct NODE{int visited;int distance;int visitedfrom_x;int visitedfrom_y;}node[MAXR][MAXC];void init_dfs(int r,int c){int i,j;for(i=0;i