Traieu els espais addicionals d'una cadena
Tenint en compte una cadena que conté molts espais consecutius, retalleu tots els espais perquè totes les paraules hagin de contenir Només un sol espai entre ells. La conversió s’ha de fer al lloc i la solució hauria de gestionar els espais posteriors i els principals i també eliminar els espais anteriors abans de la puntuació comuna com la coma de parada completa i un signe d’interrogació.
Exemples:
Input:
str = ' Hello Geeks . Welcome to GeeksforGeeks . ';
Output:
'Hello Geeks. Welcome to GeeksforGeeks.'
Input:
str = 'GeeksforGeeks';
Output:
'GeeksforGeeks'
(No change is needed)
Aquest problema és una extensió de Elimineu els espais d'una cadena determinadaMètode 1:
- La idea és mantenir 2 indicadors. Inicialment, tots dos apunten al començament de la matriu.
- El primer punter fa un seguiment de la següent posició per omplir -se a la cadena de sortida.
- El segon punter està avançat per llegir tots els caràcters de la cadena un per un.
- En trobar qualsevol caràcter no espai, el personatge es copia a la ubicació del primer punter i després es avançen els primers i el segon punters.
- Si el caràcter no espai és una coma de parada completa o un signe d’interrogació, també eliminem qualsevol espai anterior abans.
- En trobar caràcters d'espai consecutius, només es copia un espai a la ubicació del primer punter i el descans s'ignora. Els espais líders i posteriors es manegen per separat a la solució.
A continuació, es mostra la implementació de C ++ de la idea anterior.
// C++ program to implement custom trim() function #include using namespace std ; // Function to in-place trim all spaces in the // string such that all words should contain only // a single space between them. void removeSpaces ( string & str ) { // n is length of the original string int n = str . length (); // i points to next position to be filled in // output string/ j points to next character // in the original string int i = 0 j = -1 ; // flag that sets to true is space is found bool spaceFound = false ; // Handles leading spaces while ( ++ j < n && str [ j ] == ' ' ); // read all characters of original string while ( j < n ) { // if current characters is non-space if ( str [ j ] != ' ' ) { // remove preceding spaces before dot // comma & question mark if (( str [ j ] == '.' || str [ j ] == '' || str [ j ] == '?' ) && i - 1 >= 0 && str [ i - 1 ] == ' ' ) str [ i - 1 ] = str [ j ++ ]; else // copy current character at index i // and increment both i and j str [ i ++ ] = str [ j ++ ]; // set space flag to false when any // non-space character is found spaceFound = false ; } // if current character is a space else if ( str [ j ++ ] == ' ' ) { // If space is encountered for the first // time after a word put one space in the // output and set space flag to true if ( ! spaceFound ) { str [ i ++ ] = ' ' ; spaceFound = true ; } } } // Remove trailing spaces if ( i <= 1 ) str . erase ( str . begin () + i str . end ()); else str . erase ( str . begin () + i - 1 str . end ()); } // Driver Code int main () { string str = ' Hello Geeks . Welcome to' ' GeeksforGeeks . ' ; removeSpaces ( str ); cout < < str ; return 0 ; }
Java class Main { public static String removeSpaces ( String s ) { int n = s . length (); int i = 0 j = - 1 ; boolean spaceFound = false ; // Handles leading spaces while ( j < n - 1 && s . charAt ( j + 1 ) == ' ' ) { j ++ ; } // read all characters of original string while ( j < n ) { // if current characters is non-space if ( s . charAt ( j ) != ' ' ) { // remove preceding spaces before dot // comma & question mark if (( s . charAt ( j ) == '.' || s . charAt ( j ) == '' || s . charAt ( j ) == '?' ) && i - 1 >= 0 && s . charAt ( i - 1 ) == ' ' ) { s = s . substring ( 0 i - 1 ) + s . charAt ( j ) + s . substring ( i ); j ++ ; } else { // copy current character at index i // and increment both i and j s = s . substring ( 0 i ) + s . charAt ( j ) + s . substring ( i + 1 ); i ++ ; j ++ ; } // set space flag to false when any // non-space character is found spaceFound = false ; } else if ( s . charAt ( j ) == ' ' ) { // If space is encountered for the first // time after a word put one space in the // output and set space flag to true if ( ! spaceFound ) { s = s . substring ( 0 i ) + ' ' + s . substring ( i + 1 ); i ++ ; spaceFound = true ; } j ++ ; } } // Remove trailing spaces if ( i <= 1 ) { s = s . substring ( 0 i ); } else { s = s . substring ( 0 i - 1 ); } return s ; } // Driver code public static void main ( String [] args ) { String str = ' Hello Geeks . Welcome to' + ' GeeksforGeeks . ' ; str = removeSpaces ( str ); System . out . println ( str ); } }
Python3 # Python code for the above approach def removeSpaces ( s ): # n is length of the original string n = len ( s ) # i points to next position to be filled in # output string/ j points to next character # in the original string i = 0 j = - 1 # flag that sets to true is space is found spaceFound = False # Handles leading spaces while j < n - 1 and s [ j + 1 ] == ' ' : j += 1 # read all characters of original string while j < n : # if current characters is non-space if s [ j ] != ' ' : # remove preceding spaces before dot # comma & question mark if (( s [ j ] == '.' or s [ j ] == '' or s [ j ] == '?' ) and i - 1 >= 0 and s [ i - 1 ] == ' ' ): s = s [: i - 1 ] + s [ j ] + s [ i :] j += 1 else : # copy current character at index i # and increment both i and j s = s [: i ] + s [ j ] + s [ i + 1 :] i += 1 j += 1 # set space flag to false when any # non-space character is found spaceFound = False # if current character is a space elif s [ j ] == ' ' : # If space is encountered for the first # time after a word put one space in the # output and set space flag to true if not spaceFound : s = s [: i ] + ' ' + s [ i + 1 :] i += 1 spaceFound = True j += 1 # Remove trailing spaces if i <= 1 : s = s [: i ] else : s = s [: i - 1 ] return s # Driver Code str = ' Hello Geeks . Welcome to' ' GeeksforGeeks . ' str = removeSpaces ( str ) print ( str ) # This code is contributed by adityasharmadev01
C# // C# program to implement custom trim() function using System ; public class Gfg { public static void Main () { string str = ' Hello Geeks . Welcome to' + ' GeeksforGeeks . ' ; removeSpaces ( ref str ); Console . WriteLine ( str ); } // Function to in-place trim all spaces in the // string such that all words should contain only // a single space between them. public static void removeSpaces ( ref string str ) { // n is length of the original string int n = str . Length ; // i points to next position to be filled in // output string/ j points to next character // in the original string int i = 0 j = - 1 ; // flag that sets to true is space is found bool spaceFound = false ; // Handles leading spaces while ( ++ j < n && str [ j ] == ' ' ); // read all characters of original string while ( j < n ) { // if current characters is non-space if ( str [ j ] != ' ' ) { // remove preceding spaces before dot // comma & question mark if (( str [ j ] == '.' || str [ j ] == '' || str [ j ] == '?' ) && i - 1 >= 0 && str [ i - 1 ] == ' ' ) str = str . Remove ( i - 1 1 ). Insert ( i - 1 str [ j ++ ]. ToString ()); else { // copy current character at index i // and increment both i and j str = str . Remove ( i 1 ). Insert ( i str [ j ++ ]. ToString ()); i ++ ; } // set space flag to false when any // non-space character is found spaceFound = false ; } // if current character is a space else if ( str [ j ++ ] == ' ' ) { // If space is encountered for the first // time after a word put one space in the // output and set space flag to true if ( ! spaceFound ) { str = str . Remove ( i 0 ). Insert ( i ' ' ); i ++ ; spaceFound = true ; } } } // Remove trailing spaces if ( i <= 1 ) str = str . Remove ( i n - i ); else str = str . Remove ( i - 1 n - i + 1 ); } }
JavaScript // JavaScript program to implement custom trim() function // Function to in-place trim all spaces in the // string such that all words should contain only // a single space between them. function removeSpaces ( str ) { // n is length of the original string let n = str . length ; // i points to next position to be filled in // output string/ j points to next character // in the original string let i = 0 j = - 1 ; // flag that sets to true is space is found let spaceFound = false ; // Handles leading spaces while ( ++ j < n && str [ j ] == ' ' ); // read all characters of original string while ( j < n ) { // if current characters is non-space if ( str [ j ] != ' ' ) { // remove preceding spaces before dot // comma & question mark if (( str [ j ] == '.' || str [ j ] == '' || str [ j ] == '?' ) && i - 1 >= 0 && str [ i - 1 ] == ' ' ) str = str . substr ( 0 i - 1 ) + str [ j ++ ] + str . substr ( i ); else // copy current character at index i // and increment both i and j str = str . substr ( 0 i ++ ) + str [ j ++ ] + str . substr ( i ); // set space flag to false when any // non-space character is found spaceFound = false ; } // if current character is a space else if ( str [ j ++ ] == ' ' ) { // If space is encountered for the first // time after a word put one space in the // output and set space flag to true if ( ! spaceFound ) { str = str . substr ( 0 i ++ ) + ' ' + str . substr ( i ); spaceFound = true ; } } } // Remove trailing spaces if ( i <= 1 ) str = str . substr ( 0 i ); else str = str . substr ( 0 i - 1 ); return str ; } // Driver Code let str = ' Hello Geeks . Welcome to' + ' GeeksforGeeks . ' ; str = removeSpaces ( str ); console . log ( str );
Sortida:
Hello Geeks. Welcome to GeeksforGeeks.
Complexitat temporal de la solució anterior és O (N).
Espai auxiliar és o (1) ja que la conversió es fa al lloc.Mètode 2:
C++
Una altra solució que utilitza funcions predefinides a Python 3:Java#include#include int main () { std :: string input_string = ' Hello Geeks . Welcome Do you love Geeks Geeks ? ' ; std :: string output_string ; bool space_flag = false ; // Flag to check if spaces have occurred for ( size_t index = 0 ; index < input_string . length (); ++ index ) { if ( input_string [ index ] != ' ' ) { if ( space_flag ) { if ( input_string [ index ] == '.' || input_string [ index ] == '?' || input_string [ index ] == '' ) { // Do nothing } else { output_string += ' ' ; } space_flag = false ; } output_string += input_string [ index ]; } else if ( index > 0 && input_string [ index - 1 ] != ' ' ) { space_flag = true ; } } std :: cout < < output_string < < std :: endl ; return 0 ; } Python3public class Main { public static void main ( String [] args ) { String inputString = ' Hello Geeks . Welcome Do you love Geeks Geeks ? ' ; String outputString = '' ; boolean spaceFlag = false ; // Flag to check if spaces have occurred for ( int index = 0 ; index < inputString . length (); ++ index ) { if ( inputString . charAt ( index ) != ' ' ) { if ( spaceFlag ) { if ( inputString . charAt ( index ) == '.' || inputString . charAt ( index ) == '?' || inputString . charAt ( index ) == '' ) { // Do nothing } else { outputString += ' ' ; } spaceFlag = false ; } outputString += inputString . charAt ( index ); } else if ( index > 0 && inputString . charAt ( index - 1 ) != ' ' ) { spaceFlag = true ; } } System . out . println ( outputString ); } }C## Python program to Remove # extra spaces from a string input_string = ' Hello Geeks . Welcome Do you love Geeks Geeks ? ' output_string = [] space_flag = False # Flag to check if spaces have occurred for index in range ( len ( input_string )): if input_string [ index ] != ' ' : if space_flag == True : if ( input_string [ index ] == '.' or input_string [ index ] == '?' or input_string [ index ] == '' ): pass else : output_string . append ( ' ' ) space_flag = False output_string . append ( input_string [ index ]) elif input_string [ index - 1 ] != ' ' : space_flag = True print ( '' . join ( output_string ))JavaScriptusing System ; class Program { static void Main () { string inputString = ' Hello Geeks . Welcome to GeeksforGeeks Do you love Geeks Geeks ? ' ; char [] outputArray = new char [ inputString . Length ]; // Using char array for efficient string building int outputIndex = 0 ; bool spaceFlag = false ; // Flag to check if spaces have occurred for ( int index = 0 ; index < inputString . Length ; ++ index ) { if ( inputString [ index ] != ' ' ) { if ( spaceFlag ) { // Check if the current character is a punctuation mark if ( inputString [ index ] == '.' || inputString [ index ] == '?' || inputString [ index ] == '' ) { // Do nothing } else { outputArray [ outputIndex ++ ] = ' ' ; } spaceFlag = false ; } outputArray [ outputIndex ++ ] = inputString [ index ]; } else if ( index > 0 && inputString [ index - 1 ] != ' ' ) { spaceFlag = true ; } } string outputString = new string ( outputArray 0 outputIndex ); // Convert char array to string Console . WriteLine ( outputString ); } }Sortida:
Hello Geeks. Welcome to GeeksforGeeks. Do you love Geeks Geeks?
Complexitat temporal de la solució anterior és O (N).
Espai auxiliar és o (n) com s'havia de crear una altra llista.Mètode 3: (Mitjançant la funció integrada)
C++Java#include#include #include int main () { std :: string str = ' Hello Geeks . Welcome Do you love Geeks Geeks ? ' ; // Use regular expression to replace multiple spaces with a single space std :: regex pattern ( ' \ s+' ); std :: string result = std :: regex_replace ( str pattern ' ' ); // Remove leading and trailing spaces size_t firstNonSpace = result . find_first_not_of ( ' ' ); size_t lastNonSpace = result . find_last_not_of ( ' ' ); if ( firstNonSpace != std :: string :: npos && lastNonSpace != std :: string :: npos ) { result = result . substr ( firstNonSpace lastNonSpace - firstNonSpace + 1 ); } std :: cout < < result < < std :: endl ; return 0 ; } // code contributed by shinjanpatra Python3/** Java Program to remove extra spaces from a string **/ public class GFG { public static void main ( String args [] ) { String str = ' Hello Geeks . Welcome Do you love Geeks Geeks ? ' ; System . out . println ( str . replaceAll ( '\s+' ' ' ). trim ()); } }C## Python program to remove extra spaces from a string # Input string str = ' Hello Geeks . Welcome Do you love Geeks Geeks ? ' # Removing extra spaces using regex import re str = re . sub ( 's+' ' ' str ) . strip () # Printing the final string print ( str )JavaScript// C# Program to remove // extra spaces from a string using System ; class Program { static void Main ( string [] args ) { string str = ' Hello Geeks . Welcome Do you love Geeks Geeks ? ' ; // Removing extra spaces using regex and print Console . WriteLine ( System . Text . RegularExpressions . Regex . Replace ( str . Trim () @'s+' ' ' )); } }Sortida:
Hello Geeks . Welcome Do you love Geeks Geeks ?
Complexitat temporal : O (n) on n és el nombre de caràcters de la cadena.
Espai auxiliar: O (1) ja que només hi ha lletres minúscules.
Aquest article és aportat per Aarti_rathi i Aditya Goel .
