Submission #866985

#	Time	Username	Problem	Language	Result	Execution time	Memory
866985		haire	Three Friends (BOI14_friends)	Cpython 3	100 / 100	257 ms	51968 KiB

friends

n=int(input())
if n%2==0:
    print("NOT POSSIBLE")
    exit()
n//=2
s=[*input()]
 
def isValid(a,b):
    return a==b
 
def bad(i):
    temp=s[:i]+s[i+1:]
    return isValid(temp[:n],temp[n:])
 
if isValid(s[1:n+1],s[n+1:]) and isValid(s[:n],s[n:-1]):
    if s[1:n+1] != s[:n]:
        print("NOT UNIQUE")
        exit()
 
 
if isValid(s[1:n+1],s[n+1:]):
    print("".join(s[1:n+1]))
    exit()
 
if isValid(s[:n],s[n:-1]):
    print("".join(s[n:-1]))
    exit()
 
i=0
j=n+1
while i<n:
    if s[i]!=s[j]:
        wrong=i
        if bad(i):
            print("".join(s[n+1:]))
            exit()
        else:
            break
    i+=1
    j+=1
 
i=0
j=n
while i<n+1:
    if s[i]!=s[j]:
        wrong=j
        if bad(j):
            print("".join(s[:n]))
            exit()
        else:
            break
    i+=1
    j+=1
 
print("NOT POSSIBLE")

• Subtask 1: 35 / 35
• Subtask 2: 65 / 65