Submission #400848

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Source Code Expand

#!/usr/bin/env python


def read():
    raw_input()
    return raw_input()


def work(goal):
    step = 1
    
    curStr = 'b'
    
    while len(curStr) < len(goal):
        if step % 3 == 1:
            curStr = 'a' + curStr + 'c'
        elif step % 3 == 2:
            curStr = 'c' + curStr + 'a'
        elif step % 3 == 0:
            curStr = 'b' + curStr + 'b'
        step += 1
    
    print -1 if curStr != goal else step - 1


if __name__ == "__main__":
    work(read())

Submission Info

Judge Result