Thread: complete the gaps

what the second if is checking?

So your trying to write your own strcmp() function?

no !!

why do you think that

The first block is going to handle cases where the new element goes at the head of the list. The other block handles cases where the new block goes elsewhere.

The conditional statements in each case are going to be similar, using this rule - "its supposed to be sorted by length and if two words have equal length then by dictionary order" Note that there are two conditions here and they match up with the two conditional statements in each block.

The best way to figure out how to make the pointers line up is to draw up an example for yourself. The new node's going to be inserted between temp and temp2. You'll need to adjust the next pointers of both the temp node and the new node to make that happen.

i tried the first block
the next of head shoud be temp,i cant do malloc and assogng values and change head in two lines

Code:

#include <stdio.h>	
#include <stdlib.h>
#include <string.h>

typedef struct wordStruct{
	char string[256];
	struct wordStruct *next;
} wordStruct;

wordStruct * wordAlloc(char *str){
	wordStruct *temp;
	temp = (wordStruct *)malloc(sizeof(wordStruct));
	temp->next=NULL;
	strcpy(temp->string,str);
	return temp;
} 

wordStruct *insert( wordStruct *head, char *st){
	wordStruct* temp, *temp2;
	
	if(head == NULL) return wordAlloc(st);
	
	if((strlen(st)>strlen(head->string))|| ((strlen(st)==strlen(head->string) &&(strcmp(st,head->string))>1)){
		temp =(wordStruct *) malloc(sizeof(wordStruct));
		temp->string=st;
		return temp;
	}
	
	for(temp=head; temp->next ; temp = temp -> next){
		if(?? 11 ??)break;
		if( ?? 12 ??&& ?? 13 ??)break;
	}	
	
	temp2 = temp->next;
	?? 14 ??;
	?? 15 ??;
	return head;	
}

void main(){	
	char word[256];
	wordStruct *list = NULL;
	
	while(scanf("%s", word)==1)
		list = insert(list, word);				
	. . . .	
}

the this part is harder

Code:

#include <stdio.h>	
#include <stdlib.h>
#include <string.h>

typedef struct wordStruct{
	char string[256];
	struct wordStruct *next;
} wordStruct;

wordStruct * wordAlloc(char *str){
	wordStruct *temp;
	temp = (wordStruct *)malloc(sizeof(wordStruct));
	temp->next=NULL;
	strcpy(temp->string,str);
	return temp;
} 

wordStruct *insert( wordStruct *head, char *st){
	wordStruct* temp, *temp2;
	
	if(head == NULL) return wordAlloc(st);
	
	if((strlen(st)>strlen(head->string))|| ((strlen(st)==strlen(head->string) &&(strcmp(st,head->string))>0)){
		temp = insert(NULL,st);
		temp->next=head;
		return temp;
	}
	
	for(temp=head; temp->next ; temp = temp -> next){
		if(?? 11 ??)break;
		if( ?? 12 ??&& ?? 13 ??)break;
	}	
	
	temp2 = temp->next;
	?? 14 ??;
	?? 15 ??;
	return head;	
}

void main(){	
	char word[256];
	wordStruct *list = NULL;
	
	while(scanf("%s", word)==1)
		list = insert(list, word);				
	. . . .	
}

is it correct?

Code:

#include <stdio.h>	
#include <stdlib.h>
#include <string.h>

typedef struct wordStruct{
	char string[256];
	struct wordStruct *next;
} wordStruct;

wordStruct * wordAlloc(char *str){
	wordStruct *temp;
	temp = (wordStruct *)malloc(sizeof(wordStruct));
	temp->next=NULL;
	strcpy(temp->string,str);
	return temp;
} 

wordStruct *insert( wordStruct *head, char *st){
	wordStruct* temp, *temp2;
	
	if(head == NULL) return wordAlloc(st);
	
	if((strlen(st)>strlen(head->string))|| ((strlen(st)==strlen(head->string) &&(strcmp(st,head->string))>0)){
		temp = insert(NULL,st);
		temp->next=head;
		return temp;
	}
	
	for(temp=head; temp->next ; temp = temp -> next){
		if(strlen(temp->string)>strlen(st))break;
		if( (strlen(temp->string)==strlen(st))&&(strcmp(st,temp->string))>0) )break;
	}	
	
	temp2 = temp->next;
	temp->next=insert(NULL,st);
	temp->next->next=temp2;
	return head;	
}

void main(){	
	char word[256];
	wordStruct *list = NULL;
	
	while(scanf("%s", word)==1)
		list = insert(list, word);				
	. . . .	
}

Have you ever noticed that you're actually capable of working through a problem yourself when the first thing you do isn't post here and give up?

In any case - does the above code do what it's supposed to do? If it does, I guess it's correct. (Though you're still using void main, which means your code won't compile, and if I wanted to test it for you, I'd have to change it)

Originally Posted by transgalactic2

is it correct?

Code:

void main(){	
	char word[256];
	wordStruct *list = NULL;
	
	while(scanf("%s", word)==1)
		list = insert(list, word);
	. . . .
}

Looks ok barring items in red. Unusual sort though ie one which sorts lengthwise and then uses lexicography for a tie-breaker - must be a pedagogical sort .