Yaroslav has an array that consists of *n* integers. In one second Yaroslav can swap two neighboring array elements. Now Yaroslav is wondering if he can obtain an array where any two neighboring elements would be distinct in a finite time.

Help Yaroslav.
The first line contains integer *n* (1 ≤ *n* ≤ 100) — the number of elements in the array. The second line contains *n* integers *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub> (1 ≤ *a*<sub class="lower-index">*i*</sub> ≤ 1000) — the array elements.
n=int(input())
s=input()
ar=list(s[0])

for i in range(2,(2*n)-1,2):
    if(s[i] in ar):
        ar.append(s[i])
    else:
        ar.pop()


if(len(ar)==2):
    if(ar[0]==ar[1]):
        print("NO")
    else:
        print("YES")
elif(len(ar)>2):
    print("NO")
else:
    print("YES")

