A = str(input()).split(' ')
y = int(A[0])
m = int(A[1])
d = int(A[2])
if m in (1,3,5,7,8,10,12):
    if d in range(1,32):
        print("%04d/%02d/%02d"%(y,m,d))
    else:
        print("日期錯誤")
elif m in (4,6,9,11):
    if d in range(1,31):
        print("%04d/%02d/%02d"%(y,m,d))
    else:
        print("日期錯誤")
elif m==2:
    if y%400==0 or (y%4==0 and y%100!=0):
        if d in range(1,30):
            print("%04d/%02d/%02d"%(y,m,d))
        else:
            print("日期錯誤")
    else:
        if d in range(1,29):
            print("%04d/%02d/%02d"%(y,m,d))
        else:
            print("日期錯誤")
else:
    print("日期錯誤")