def isFibo(n):
    # Write your code here
    if n==0 or n==1:
        return "IsFibo"
    i_th=0
    i2_th=1
    index=1
    while index<=n:
        if i_th+i2_th==n:
            return "IsFibo"
        i_th = i2_th
        i2_th = index
        index = i_th + i2_th
    if index==n:
        return "IsFibo"
    return "IsNotFibo"