class dian:
    def _init_(self):
        self.dj=0
        self.sl=0
a=[]
for i in range(6):
    a.append(dian())
    a[i].dj=chr(ord("A")+i)
    a[i].sl=0
n=int(input())
sr=input().split()
for i in range(n):
    g=int(sr[i])
    if(g<20):
        a[5].sl=a[5].sl+1
    elif(g<29):
        a[4].sl=a[4].sl+1
    elif(g<39):
        a[3].sl=a[3].sl+1
    elif(g<49):
        a[2].sl=a[2].sl+1
    elif(g<59):
        a[1].sl=a[1].sl+1
    else:
        a[0].sl=a[0].sl+1
for i in range(6-1):
    for j in range(6-i-1):
        if(a[j].sl<a[j+1].sl):
            t=a[j]
            a[j]=a[j+1]
            a[j+1]=t
        elif(a[j].sl==a[j+1].sl and a[j].dj>a[j+1].dj):
            t=a[j]
            a[j]=a[j+1]
            a[j+1]=t
for i in range(6):
    print("{}:{}".format(a[i].dj,a[i].sl))
/**************************************************************
	Problem: 1314
	User: admin
	Language: Python
	Result: Accepted
	Time:93 ms
	Memory:34480 kb
****************************************************************/