def solution(x, y):
    prisonerID = 0
    
    #traverse down the x axis first
    i = x
    while i > 0:
        prisonerID += i
        i -= 1
    
    #traverse up the y axis second
    while y > 1:
        prisonerID += x
        x += 1
        y -= 1
            
    #return the string of the id
    return str(prisonerID)
        
        
print "Case 1,1: " + solution(1,1)