Normalize.c

/*Normalize takes a character array and removes leading/trailing blankspaces.  Additionally, it makes any uppercase letter
lowercase, and collapses spaces that contain more than one space into one space. */

int normalize(char *buf, /* The character array containing the string to be normalized*/
              int len    /* the size of the original character array */)
{
  //Print initial array	
  int j=0;
  while(j<len){
    
      printf("%c", (char)buf[j]);
      j++;
    }
  printf("\n");


  char *write=buf; 							//points to writer
  char *read=buf;  							//points to reader
  int i;           							//array index
  int ctr=0;       							//number of deleted characters
  
 for (i=0; i<len; i++){ 						//for each element in the array
	
      if(isspace(*read)!=0){					        //if what read is pointing to is a space
          
       	if(write == buf){					       //if nothing has been written yet
    			
      		while(isspace(*read) != 0){		               //while read is still pointing to a blank
        			
          		read++;				               //increment the location of read
           		ctr++;            			       //increment the amount of unused characters
        		}
      		*write =getLower((int) *read); 		        	//break out of loop and assign write its first character
          	}

        if (isspace(buf[i-1])!=0){				        //if there are two consecutive spaces
         
           	while (isspace(*read) != 0){			       //while there is more than one consecutive space
          
            		read++;						//increment read pointer
          	  	ctr++;					       //increment the amount of unused characters
          	}
          }

       if(buf[i+1]==NULL){          					//if there is one extra trailing space
        ctr++;						                //record it to be deleted
          }
       }

      *write = getLower((int)*read);					//write what is in read

      write++;								//increment write
      read++;								//increment read
    }
  
   int temp = ctr;								
   while(temp > 0){							//for each extra space at the end
    
     	read=NULL;							//assign each extra space null to delete them
     	temp--;
    }

  //print normalized array
  int k=0;
  while(k<len){
    
      printf("%c", (char)buf[k]);
      k++;
    }
  printf("\n");

  	return len - ctr; 						//return the size of the normalized array
}