CareerCup

void RemoveSpaces(char* src, int len)
{
   char* copyFrom = src, *copyTo = src;

   for(int i = 1; i < len; ++i )
   {
      if(src[i-1] == ' ' && src[i]==' ')
      {
         ++copyFrom;
      }
      else
      {
         *copyTo++ = *copyFrom++;
      }
   }

   *copyTo = 0;
}

int main(int argc, char** argv)
{
   char arr[] = "Test String    to be  displayed ";
   RemoveSpaces(arr, strlen(arr));

   cout << arr << endl;
   return 0;
}

Assuming " " to be replaced....

String a = "There are multiple spaces";
while (a.contains(" ")){
a=a.replace(" ", " ");

}
System.out.println(a);

}

String a = "There are          multiple                      spaces";
		while (a.contains("  ")){
		a=a.replace("  ", " ");
	
	}
	System.out.println(a);
	
	}

This is a version of a possible solution:

string str = "Test String to be displayed";
char *ptr = (char *)str.c_str();
int index = 0,w_start = 0,w_end = 0;

while(*ptr) {
w_end = w_start;
while(*ptr && *ptr != ' '){
ptr++;
w_end++;
}
while(w_start < w_end)
str[index++] = str[w_start++];
str[index++] = ' ';

while(*ptr && *ptr == ' '){
w_start++;
ptr++;
}
}
for(; index < str.size(); index++)
str[index] = '\0';

cout << "Final: " << str << endl;

This code is very simple.
Just compare every element with every other element. If they both are spaces( in my prog i did for dashes!) they replace with a single dash and decrement the count of i by one.
Hope it helps!

private static void MultipleSpaces(){
String str = "Test-String-----to-be--displayed--";
for(int i=0;i<str.length()-1;i++){
if(str.charAt(i)=='-' && str.charAt(i+1)=='-'){
i--;
str=str.replace("--","-");
}
}
System.out.println(str);
}

Using Perl...

$str=~ s/\s+/-/g;

1. Should not use Perl REGEX
2. Should not use any extra character string (char arr[size])

Hint - use two char pointers on the same string

#include<stdio.h>
#include<string.h>
int main()
{
char str[50];
int len,i=0,j,spaces=0;
clrscr();
printf("\n Enter the String\n");
gets(str);
len=strlen(str);
printf("\n Length of the String is %d\n",len);
for(j=0;j<=len;j++)
{
if(str[j]==' ')
spaces++;
else
{
if(spaces>0)
{
str[i]=' ';
i++;
}
str[i]=str[j];
i++;
spaces=0;
}
}
str[i]='\0';
printf("Result String %s",str);
}

#include <stdio.h>

int main()
{
char str[] = " This is my junk code";
char *p, *q;

p = q = str;
while (*p) {
while (*p == ' ' && *p != '\0')
p++;
if (*(p-1) == ' ' && *p != ' ')
*q++ = *(p -1);
*q++ = *p++;
}
*q = *p;
fprintf( stderr, "The value is :%s\n", str);
return 0;
}

This code works in JAVA

String test = " hey how are you";
test = test.replaceAll("\\s+", " ");
System.out.println(test);

void replace(char *str)
{
    int i = 1; j = 1;        //notei and j = 1, not 0   
    char *cur = str;
    while(cur[i])
    {
        if(cur[i] == ' ')
        {
            if(cur[i-1] == ' ')        //first occurence
            {
                //ignore it
             }
        }
        else
        {
           cur[j++] = cur[i];
        }
}

rplace(char * c,int l)
{
char *p,*q;
p=c;
q=c;
for(i=1;i<l;i++)
if(p[i-1]==' ' && p[i]==' ')
{
++p;
}
else
{
*q++=*q++;
}
}
*q='\0';
}

#define TrimCharacter '-'
char * Trim(char * inputString,int l)
{
    char *p,*q;
    q = p = inputString;
    while(*p){
        if((*p != TrimCharacter) || (*q != TrimCharacter)) {
            *q = *p;
            q++;
        }
        p++;
    }
    *q = 0;
    return inputString;
}

<pre lang="c++" line="1" title="CodeMonkey19636" class="run-this">#include<iostream>
#include<string>

using namespace std;

int main()
{
string s=" Hello, how r u???????";

int pos,i=0;


for(i=0;i<s.length();i++)
{
if(s[i]==' ')
{ if(i!=0)
i=i+1;
while(s[i]==' ')
{
s.erase(s.begin()+i);
}
}
}

cout<<s<<"\n";

return 0;

}</pre><pre title="CodeMonkey19636" input="yes">
</pre>

public class nr_LimitSpaceBetweenWordsInAStringToOne
{

/**
* @param args
*/
public static void main(String[] args)
{
String s = "Test String to be displayed ";
//String s = "AA B C D";
int count = 0;
for(int i=0;i<s.length();i++)
{
count = 0;
while(i<s.length() && s.charAt(i)==' ')
{
i++;
count++;
}

if(count > 1)
{
System.out.println("i= "+i+" count= "+count);
s=s.substring(0,i-count+1)+s.substring(i,s.length());
System.out.println(s);
i = 0;
}
}
System.out.println("");
System.out.println("Final String after removing all extra spaces is: ");
System.out.println(s);
}
}

In ruby we could just do 

s = "Test string   to be            displayed" 
s.gsub!(/\s+/,' ')
p s 
# =>"Test string to be displayed"