
            
            
              python
              
              
            
          
          class Solution:
    def searchMatrix(self, matrix: List[List[int]], target: int) -> bool:
        r = len(matrix)
        c = len(matrix[0])
        for i in range(r):
            for j in range(c):
                if matrix[i][j]==target:
                    return True
                elif matrix[i][j]>target:
                    break
        return False
        