output_description: Print the necessary number of candies in total.
  
  * * *
input_description: The input is given from Standard Input in the following format:
  
      
      
      N
attempt: n ＝ input()
  sum=0
  for i in range(1,n+1):
      sum+=i
  print(sum)
problem_description: Statement
  
  There are N children in AtCoder Kindergarten. Mr. Evi will arrange the
  children in a line, then give 1 candy to the first child in the line, 2
  candies to the second child, ..., N candies to the N-th child. How many
  candies will be necessary in total?
samples: [{"input": "3", "output": "6\n    \n\nThe answer is 1+2+3=6.\n\n* * *"}, {"input": "10", "output": "55\n    \n\nThe sum of the integers from 1 to 10 is 55.\n\n* * *"}, {"input": "1", "output": "1\n    \n\nOnly one child. The answer is 1 in this case."}]