[프로그래머스/python] 체육복

def solution(n, lost, reserve):
    answer = 0
    total = list()
    
    for i in range(n):
        total.append(1)
    
    for i in lost:
        total[i-1] -= 1
    
    for i in reserve:
        total[i-1] += 1 
  
    for i in range(len(total)):
        if total[i] == 2:
            if i-1 >= 0:
                if total[i-1] == 0:
                    total[i-1] += 1
                    total[i] -= 1
        if total[i] == 2:
            if i+1 < len(total):
                if total[i+1] == 0:
                    total[i+1] += 1
                    total[i] -= 1
                    
    for student in total:
        if student >= 1:
            answer += 1
                    
    return answer