#Challenge
#Have the function SimpleAdding(num) add up all the numbers from 1 to num. For example: if the input is 4 then your program should return 10 because 1 + 2 + 3 + 4 = 10. For the test cases, the parameter num will be any number from 1 to 1000. 
#Sample Test Cases
#Input:12
#Output:78

#Input:140
#Output:9870

def SimpleAdding(num): 
    add = 0
    # code goes here 
    for i in range(0, num):
      add+= i+1

    return add
    
# keep this function call here  
print(SimpleAdding(input())) 


  
