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hihocoder1144: 01-string 2. Analysis 3. Solution(s)

admin 11月 12, 2020 0

Description

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Given two integers n and m, is there a string containing exactly n “0”s and m “1”s while it doesn’t contain any substring of “001” or “11”?

If such strings exist output the lexicographically smallest one. Otherwise output NO.

Input

One line with two integers, determining n and m (0<=n,m<=100000,0<n+m)

Output

One line with the lexicographically smallest string which is the answer or NO.

Sample Input

2 3

Sample Output

2. Analysis

3. Solution(s)

(n, m) = (int(x) for x in raw_input().split())
if n < m-1:
    print "NO"
else:
    res = ""
    if n >= m:
        for i in range(m):
            res += "01"
        for i in range(n-m):
            res += "0"
    elif n == m-1:
        for i in range(n):
            res += "10"
        res += "1"
    print res