




import decimal

def 					SCREAMING_SNAKE_CASE							(   )			->     int:
     a      =      0
     a      =      decimal.Context(prec=1_05)
     for i in range(2		,					1_00):
          a      =      decimal.Decimal(__UpperCamelCase)
          a      =      number.sqrt(__UpperCamelCase)
          if len(str(__UpperCamelCase)) > 1:
               answer += int(str(__UpperCamelCase)[0])
               a      =      str(__UpperCamelCase)[2:1_01]
               answer += sum(int(__UpperCamelCase) for x in sqrt_number_str)
     return answer


if __name__ == "__main__":
   import doctest

   doctest.testmod()
   print(F'{solution() = }')



"""simple docstring"""

from __future__ import annotations




def 			lowercase__  (    lowerCAmelCase :    Dict       )       ->					Optional[int]:






    """simple docstring"""




    global graph, reversed_graph, scc, component, visit, stack
    if visit[u]:
        return
    UpperCAmelCase  	=    True
    for v in graph[u]:
        dfs(lowerCAmelCase       )
    stack.append(lowerCAmelCase       )




def 			lowercase__  (    lowerCAmelCase :    Optional[int]       )       ->					int:






    """simple docstring"""




    global graph, reversed_graph, scc, component, visit, stack
    if visit[u]:
        return
    UpperCAmelCase  	=    True
    component.append(lowerCAmelCase       )
    for v in reversed_graph[u]:
        dfsa(lowerCAmelCase       )




def 			lowercase__  (    )       ->					List[str]:






    """simple docstring"""




    global graph, reversed_graph, scc, component, visit, stack
    for i in range(lowerCAmelCase       ):
        dfs(lowerCAmelCase       )
    UpperCAmelCase  	=    [False] * n
    for i in stack[::-1]:
        if visit[i]:
            continue
        UpperCAmelCase  	=    []
        dfsa(lowerCAmelCase       )
        scc.append(lowerCAmelCase       )
    return scc


if __name__ == "__main__":
   # n - no of nodes, m - no of edges
   SCREAMING_SNAKE_CASE_    ,  SCREAMING_SNAKE_CASE_			    =  list(map(int, input().strip().split()))

   SCREAMING_SNAKE_CASE_			    =  [[] for _ in range(n)]  # graph
   SCREAMING_SNAKE_CASE_			    =  [[] for i in range(n)]  # reversed graph
   # input graph data (edges)
   for _ in range(m):
      SCREAMING_SNAKE_CASE_    ,  SCREAMING_SNAKE_CASE_			    =  list(map(int, input().strip().split()))
      graph[u].append(v)
      reversed_graph[v].append(u)

   SCREAMING_SNAKE_CASE_			    =  []
   SCREAMING_SNAKE_CASE_			    =  [False] * n
   SCREAMING_SNAKE_CASE_			    =  []
   SCREAMING_SNAKE_CASE_			    =  []
   print(kosaraju())



