L[i][j] ≥ L[i-1][j] ∧ # больше от элемента над собой
L[i][j] ≥ L[i+1][j] ∧ # больше от элемента под собой
L[i][j] ≥ L[i][j+1] ∧ #больше от элемента с права 
L[i][j] ≥ L[i][j-1]  ^ # больше от элемента с лева 

class Peak:
    """..."""
    def __init__(self, L):
        self.L = L[:]
        self.n = len(self.L)
        self.m = len(self.L[0])
    def get_dim(self):
        return (self.n, self.m)
    def get_val(self, loc):
        return self.L[loc[0]][loc[1]]
    def next_element(self, loc):
        if loc[1] < self.m - 1:
            return loc[0], loc[1] + 1
        else:
            if loc[0] < self.n - 1:
                return loc[0] + 1, 0
            else:
                return -1
        
    def greedy_ascent(self, start=(0,0)):
        """..."""
        pass
if __name__ == "__main__":
    A = [[1,   2,  3,  4],
         [14, 15, 16,  5],
         [13, 18, 17,  6],
         [12,  9,  3,  7],
         [11, 10,  9,  8]]

class Peak:
    """..."""
    def __init__(self, L):
        self.L = L[:]
        self.n = len(self.L)
        self.m = len(self.L[0])
        self.OL = []
    def get_dim(self):
        return (self.n, self.m)
    def get_val(self, loc):
        return self.L[loc[0]][loc[1]]
    def next_element(self, loc):
        if loc[1] < self.m - 1:
            return loc[0], loc[1] + 1
        else:
            if loc[0] < self.n - 1:
                return loc[0] + 1, 0
            else:
                return -1
    def get_val(self, x, y, p=(1, 0)):
        for i, j in [(x + p[0], y + p[1])] + [(x+1, y), (x, y+1), (x, y-1), (x-1, y)]:
            if i < 0 or j < 0 or i >= self.m or j >= self.n or (i, j) in self.OL:
                continue
            if self.L[j][i] >= self.L[y][x]:
                self.OL.append((i, j))
                return (i, j, (i-x, j-y))
        return (x, y, [])
    def greedy_ascent(self, start=(0,0)):
        x, y, p = self.get_val(*start)
        while p:
            x, y, p = self.get_val(x, y, p)
        return x, y