Kun merkkijono on annettu, meidän on tarkistettava, onko tästä merkkijonosta mahdollista tehdä palindromi, kun siitä on poistettu täsmälleen yksi merkki.
Esimerkkejä:
Input : str = abcba Output : Yes we can remove character ‘c’ to make string palindrome Input : str = abcbea Output : Yes we can remove character ‘e’ to make string palindrome Input : str = abecbea It is not possible to make this string palindrome just by removing one character
Voimme ratkaista tämän ongelman etsimällä yhteensopimattomuuden sijainnin. Aloitamme merkkijonon kiertämisen pitämällä molemmissa päissä kahta osoitinta, jotka kulkevat kohti keskikohtaa jokaisen iteraation jälkeen tämä iteraatio pysähtyy, kun löydämme ristiriidan, koska on sallittua poistaa vain yksi merkki. Tässä on kaksi vaihtoehtoa
Epäsuhtaessa joko poista vasemmalla osoittimella osoittama merkki tai oikealla osoittimella osoittama merkki.
int merkkijonomuunnos Javassa
Tarkistamme molemmat tapaukset muista, koska olemme kulkeneet yhtä monta askelta molemmilta puolilta, tämän keskimerkkijonon pitäisi myös olla palindromi yhden merkin poistamisen jälkeen, joten tarkistamme kaksi osamerkkijonoa poistamalla vasemman merkin ja toisen poistamalla oikean merkin ja jos toinen niistä on palindromi, voimme tehdä täydellisen merkkijonon palindromin poistamalla vastaavan merkin ja jos kumpikaan ei ole mahdollista tehdä täydellistä merkkijonoa. palindromi tietyn rajoituksen alaisena.
Toteutus:
C++// C/C++ program to check whether it is possible to make // string palindrome by removing one character #include
// Java program to check whether // it is possible to make string // palindrome by removing one character import java.util.*; class GFG { // Utility method to check if // substring from low to high is // palindrome or not. static boolean isPalindrome(String str int low int high) { while (low < high) { if (str.charAt(low) != str.charAt(high)) return false; low++; high--; } return true; } // This method returns -1 if it is // not possible to make string a palindrome. // It returns -2 if string is already // a palindrome. Otherwise it returns // index of character whose removal can // make the whole string palindrome. static int possiblePalinByRemovingOneChar(String str) { // Initialize low and right // by both the ends of the string int low = 0 high = str.length() - 1; // loop until low and // high cross each other while (low < high) { // If both characters are equal then // move both pointer towards end if (str.charAt(low) == str.charAt(high)) { low++; high--; } else { /* * If removing str[low] makes the * whole string palindrome. We basically * check if substring str[low+1..high] * is palindrome or not. */ if (isPalindrome(str low + 1 high)) return low; /* * If removing str[high] makes the whole string * palindrome. We basically check if substring * str[low+1..high] is palindrome or not. */ if (isPalindrome(str low high - 1)) return high; return -1; } } // We reach here when complete string // will be palindrome if complete string // is palindrome then return mid character return -2; } // Driver Code public static void main(String[] args) { String str = 'abecbea'; int idx = possiblePalinByRemovingOneChar(str); if (idx == -1) System.out.println('Not Possible'); else if (idx == -2) System.out.println('Possible without ' + 'removing any character'); else System.out.println('Possible by removing' + ' character at index ' + idx); } } // This code is contributed by // sanjeev2552
# Python program to check whether it is possible to make # string palindrome by removing one character # Utility method to check if substring from # low to high is palindrome or not. def isPalindrome(string: str low: int high: int) -> bool: while low < high: if string[low] != string[high]: return False low += 1 high -= 1 return True # This method returns -1 if it # is not possible to make string # a palindrome. It returns -2 if # string is already a palindrome. # Otherwise it returns index of # character whose removal can # make the whole string palindrome. def possiblepalinByRemovingOneChar(string: str) -> int: # Initialize low and right by # both the ends of the string low = 0 high = len(string) - 1 # loop until low and high cross each other while low < high: # If both characters are equal then # move both pointer towards end if string[low] == string[high]: low += 1 high -= 1 else: # If removing str[low] makes the whole string palindrome. # We basically check if substring str[low+1..high] is # palindrome or not. if isPalindrome(string low + 1 high): return low # If removing str[high] makes the whole string palindrome # We basically check if substring str[low+1..high] is # palindrome or not if isPalindrome(string low high - 1): return high return -1 # We reach here when complete string will be palindrome # if complete string is palindrome then return mid character return -2 # Driver Code if __name__ == '__main__': string = 'abecbea' idx = possiblepalinByRemovingOneChar(string) if idx == -1: print('Not possible') else if idx == -2: print('Possible without removing any character') else: print('Possible by removing character at index' idx) # This code is contributed by # sanjeev2552
// C# program to check whether // it is possible to make string // palindrome by removing one character using System; class GFG { // Utility method to check if // substring from low to high is // palindrome or not. static bool isPalindrome(string str int low int high) { while (low < high) { if (str[low] != str[high]) return false; low++; high--; } return true; } // This method returns -1 if it is // not possible to make string a palindrome. // It returns -2 if string is already // a palindrome. Otherwise it returns // index of character whose removal can // make the whole string palindrome. static int possiblePalinByRemovingOneChar(string str) { // Initialize low and right // by both the ends of the string int low = 0 high = str.Length - 1; // loop until low and // high cross each other while (low < high) { // If both characters are equal then // move both pointer towards end if (str[low] == str[high]) { low++; high--; } else { /* * If removing str[low] makes the * whole string palindrome. We basically * check if substring str[low+1..high] * is palindrome or not. */ if (isPalindrome(str low + 1 high)) return low; /* * If removing str[high] makes the whole string * palindrome. We basically check if substring * str[low+1..high] is palindrome or not. */ if (isPalindrome(str low high - 1)) return high; return -1; } } // We reach here when complete string // will be palindrome if complete string // is palindrome then return mid character return -2; } // Driver Code public static void Main(String[] args) { string str = 'abecbea'; int idx = possiblePalinByRemovingOneChar(str); if (idx == -1) Console.Write('Not Possible'); else if (idx == -2) Console.Write('Possible without ' + 'removing any character'); else Console.Write('Possible by removing' + ' character at index ' + idx); } } // This code is contributed by shivanisinghss2110
<script> // JavaScript program to check whether // it is possible to make string // palindrome by removing one character // Utility method to check if // substring from low to high is // palindrome or not. function isPalindrome(str low high) { while (low < high) { if (str.charAt(low) != str.charAt(high)) return false; low++; high--; } return true; } // This method returns -1 if it is // not possible to make string a palindrome. // It returns -2 if string is already // a palindrome. Otherwise it returns // index of character whose removal can // make the whole string palindrome. function possiblePalinByRemovingOneChar(str) { // Initialize low and right // by both the ends of the string var low = 0 high = str.length - 1; // loop until low and // high cross each other while (low < high) { // If both characters are equal then // move both pointer towards end if (str.charAt(low) == str.charAt(high)) { low++; high--; } else { /* * If removing str[low] makes the * whole string palindrome. We basically * check if substring str[low+1..high] * is palindrome or not. */ if (isPalindrome(str low + 1 high)) return low; /* * If removing str[high] makes the whole string * palindrome. We basically check if substring * str[low+1..high] is palindrome or not. */ if (isPalindrome(str low high - 1)) return high; return -1; } } // We reach here when complete string // will be palindrome if complete string // is palindrome then return mid character return -2; } // Driver Code var str = 'abecbea'; var idx = possiblePalinByRemovingOneChar(str); if (idx == -1) document.write('Not Possible'); else if (idx == -2) document.write('Possible without ' + 'removing any character'); else document.write('Possible by removing' + ' character at index ' + idx); // this code is contributed by shivanisinghss2110 </script>
Lähtö
Not Possible
Aika monimutkaisuus: O(N)
Tilan monimutkaisuus: O(1)
Luo tietokilpailu