# Palindrome Index

### Problem Statement :

```Given a string of lowercase letters in the range ascii[a-z], determine the index of a character that can be removed to make the string a palindrome. There may be more than one solution, but any will do. If the word is already a palindrome or there is no solution, return -1. Otherwise, return the index of a character to remove.

Example

s = "bcbc"

Either remove 'b' at index 0 or 'c' at index 3.

Function Description

Complete the palindromeIndex function in the editor below.

palindromeIndex has the following parameter(s):

string s: a string to analyze

Returns

int: the index of the character to remove or -1.

Input Format

The first line contains an integer q, the number of queries.
Each of the next q lines contains a query string s.

Constraints

1  <=   q  <= 20
1  <=   length of s  <=  10^5 + 5

All characters are in the range ascii[a-z].```

### Solution :

```                            ```Solution in C :

In  C++  :

#include<stdio.h>
#include<string.h>
char a[1000005];
char b[1000005];
int is(char *a, int n){
int i;
for(i=0;i<n/2;i++)if(a[i]!=a[n-1-i])return i;
return -1;
}
int main(){
int t;
scanf("%d",&t);
while(t--){

scanf("%s",&a);
int l = strlen(a);
int x = is(a,l);
if(x==-1){
printf("-1\n");
}
else {
int i;
int j=0;
for(i=0;a[i];i++){
if(i!=x)b[j++] = a[i];

}
if(is(b,l-1)==-1)printf("%d\n",x);
else printf("%d\n",l-1-x);
}
}
}

In  Java  :

import java.util.*;

public class Solution {

static boolean isPalidrom(String s, int i, int j) {
while (i < j) {
if (s.charAt(i++) !=  s.charAt(j--)) {
return false;
}
}
return true;
}

public static void main(String[] args) {

Scanner in = new Scanner(System.in);

int T = in.nextInt();

for (int t = 0; t < T; t++) {
String s = in.next();

int i = 0;
int j = s.length() - 1;
while (i < j) {
if (s.charAt(i) != s.charAt(j)) {
if (isPalidrom(s,i,j-1)) {
System.out.println(j);
} else {
System.out.println(i);
}
break;
}
i ++;
j --;
}

if (i >= j) {
System.out.println(-1);
}
}

}

}

In   C :

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
int main()
{
int t,i,flag,len,ans,j,stop;
char *str;
str = (char *) malloc(sizeof(char)*100005);
scanf("%d",&t);
while(t>0)
{
scanf("%s",str);
len=strlen(str);
ans=-1;
stop=0;
flag=1;
while(stop==0)
{
i=0;
while(i<len/2 && ans==-1)
{
if(str[i]!=str[len-i-1])
{
ans=i;
j=i+1;
while(j<=len/2 && flag==1)
{
if(str[j]!=str[len-j])
{
flag=0;
}
j++;
}
if(flag==1)
{
stop=1;
}
else
flag=1;
if(stop==0)
{
ans=len-i-1;
j=i;
while(j<=len/2 && flag==1)
{
if(str[j]!=str[len-j-2])
{
flag=0;
}
j++;
}
if(flag==1)
{
stop=1;
}
else
flag=1;
}
}
i++;
}
if(ans==-1)
{
stop=1;
}
}
printf("%d\n",ans);
t--;
}
return 0;
}

In   Python3  :

t = int(input())

def is_palindrome(s):
return s == s[::-1]

def solve(s):
i, j = 0, len(s) - 1
while (i < j) and (s[i] == s[j]):
i += 1
j -= 1
if i == j:
return 0
if is_palindrome(s[i + 1 : j + 1]):
return i
if is_palindrome(s[i:j]):
return j
raise AssertionError

for _ in range(t):
print(solve(input()))```
```

## View More Similar Problems

Meera teaches a class of n students, and every day in her classroom is an adventure. Today is drawing day! The students are sitting around a round table, and they are numbered from 1 to n in the clockwise direction. This means that the students are numbered 1, 2, 3, . . . , n-1, n, and students 1 and n are sitting next to each other. After letting the students draw for a certain period of ti

## Mr. X and His Shots

A cricket match is going to be held. The field is represented by a 1D plane. A cricketer, Mr. X has N favorite shots. Each shot has a particular range. The range of the ith shot is from Ai to Bi. That means his favorite shot can be anywhere in this range. Each player on the opposite team can field only in a particular range. Player i can field from Ci to Di. You are given the N favorite shots of M

## Jim and the Skyscrapers

Jim has invented a new flying object called HZ42. HZ42 is like a broom and can only fly horizontally, independent of the environment. One day, Jim started his flight from Dubai's highest skyscraper, traveled some distance and landed on another skyscraper of same height! So much fun! But unfortunately, new skyscrapers have been built recently. Let us describe the problem in one dimensional space

## Palindromic Subsets

Consider a lowercase English alphabetic letter character denoted by c. A shift operation on some c turns it into the next letter in the alphabet. For example, and ,shift(a) = b , shift(e) = f, shift(z) = a . Given a zero-indexed string, s, of n lowercase letters, perform q queries on s where each query takes one of the following two forms: 1 i j t: All letters in the inclusive range from i t

## Counting On a Tree

Taylor loves trees, and this new challenge has him stumped! Consider a tree, t, consisting of n nodes. Each node is numbered from 1 to n, and each node i has an integer, ci, attached to it. A query on tree t takes the form w x y z. To process a query, you must print the count of ordered pairs of integers ( i , j ) such that the following four conditions are all satisfied: the path from n

## Polynomial Division

Consider a sequence, c0, c1, . . . , cn-1 , and a polynomial of degree 1 defined as Q(x ) = a * x + b. You must perform q queries on the sequence, where each query is one of the following two types: 1 i x: Replace ci with x. 2 l r: Consider the polynomial and determine whether is divisible by over the field , where . In other words, check if there exists a polynomial with integer coefficie