[백준] 5단계 - 1065번 (파이썬)

1065번

https://www.acmicpc.net/problem/1065

 

 

 

def counting(n):
    num = 0
    for i in range(1, n+1):
        if i<=99:
            num += 1 
        else:
            a = i//100
            b = (i-a*100)//10
            c = i-a*100-b*10    
            if a-b == b-c:
                num +=1
    print(num)

counting(int(input()))