**Lexicographically Smallest Non-Palindromic String - Amazon Top Interview Questions**

### Problem Statement :

You are given a lowercase alphabet string s that is a palindrome. Update one character such that s is no longer a palindrome and is lexicographically smallest. Constraints 2 ≤ n ≤ 100,000 where n is the length of s Example 1 Input s = "racecar" Output "aacecar" Explanation We can change the first "r" to "a" to get the

### Solution :

` ````
Solution in C++ :
string solve(string s) {
for (int i = 0; i < s.size() / 2; i++) {
if (s[i] != 'a') {
s[i] = 'a';
return s;
}
}
s[s.size() - 1] = 'b';
return s;
}
```

` ````
Solution in Python :
class Solution:
def solve(self, s):
s = list(s)
n = len(s)
for i in range(0, n // 2):
if s[i] != "a":
s[i] = "a"
return "".join(s)
s[n - 1] = "b"
if n < 2:
return "-1"
else:
return "".join(s)
```

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