find word and insert another word after that in text

Hi,
I have text (string) and I want to find a given word (it's ok!) and then insert another given word after the first word.
The original string is beeing copied into a new string.
But something is going wrong!!!

Where is my mistake?

Thanks in advance...

(I have some patches...)

Code:

---

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
//insert "new_word" after each occurence of "word"
int main(){
char A[100]="In the sentence words the and the.";
char B[200]="";
char *word="the";
char *new_word="com";
char *p;
int word_count=0;
int i,j,word_index;
int found,position;

i=0;
j=0;
found=0;

while(A[i]!='\0'){
  word_index=0;
  position=i;
  while(A[i]==word[word_index]){//we found same letters
      B[j]=A[i];//copy A to B letter by letter
      printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);//getchar();
      i++;j++;word_index++;//increment indices
      printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);//getchar();
      printf("A: %s\n",A);
      printf("B: %s\n",B);
  }
  if (word_index==strlen(word)) {//word was found
      found=1;
      printf("position=%d\n",position);
      printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);//getchar();
      B[j]=' ';
      j++;
      strcat(B,new_word);//copy new_word to B[] after word
      printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);//getchar();
      printf("A: %s\n",A);
      printf("B: %s\n",B);
      j=j+strlen(new_word)+1;//increment j
      B[j]=' ';
      printf("A: %s\n",A);
        printf("B: %s\n",B);
      i++;j++;
      continue;//exit while loop and continue parsing
  }
  else{
        B[j]=A[i];//else continue copying A to B
        printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);//getchar();
        printf("A: %s\n",A);
        printf("B: %s\n",B);
        i++;j++;
        }
}
if(!found) printf("\"%s\" not found!\n",word);
puts(A);
puts(B);
getchar();

return 0;
}

---

Do you want to insert the new word or replace the old word? In other words, what is the expected ending values for A and B in your example?

Quote:

---

Originally Posted by c99tutorial

Do you want to insert the new word or replace the old word? In other words, what is the expected ending values for A and B in your example?

---

We find "the" and after each occurence of "the" we add the word "com".
output:
A: (the same)
B:"In the com sentence words the com and the com."

thanks in advance..

If you insert "com" after every instance of "the", then shouldn't the result be like this:

B: "In thecom sentence words thecom and thecom."

Where does the extra space come from?

Quote:

---

Originally Posted by c99tutorial

If you insert "com" after every instance of "the", then shouldn't the result be like this:

B: "In thecom sentence words thecom and thecom."

Where does the extra space come from?

---

I mean that "com" is a new word..the word "the" remains the same...

Yes, so if you find instances of "the" and insert "com" afterwards, it would do this:

before: "In the sentence words the and the."
after: "In thecom sentence words thecom and thecom."

The total number of spaces in the string should remain the same, because spaces are not involved in the search and insertion strings ("the" and "com")

Yes, I agree with you...
But my program doesn't work properly....where is my mistake??

Quote:

---

Originally Posted by xiromdim

where is my mistake??

---

Did you write out pseudocode first before writing the code? Did you consider a simple base case. For example, in general there are multiple times when the substring occurs. But to begin with you can consider what you need to do if it only occurs once. It will help in building an iterative solution

Example:

s: "The est population"
t: ""
needle: "est"
insertion: "imated"

With this, the expected output after running should have this result
t: "The estimated population"

ok! I fixed it!
I made it with pointers, whose, IMO, are better implementation for manipulating a C string...
I'm expecting your comments....

Code:

---

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
//insert "new_word" after each occurence of "word"
int main(){
char A[100]="in the the";
char B[200]="";
char *word="the";
char *new_word="com";
char *a,*b,*w,*nw;
int word_count=0;
int i,j,word_index;
int found,position;

a=A;
b=B;
w=word;
nw=new_word;
found=0;

while(*a!='\0'){
        w=word;
  //position=i;
  while(*a==*w&& *a!='\0'){//we found same letters
      *b=*a;//copy A to B letter by letter
      //printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);getchar();
      a++;b++;w++;//increment indices
      //printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);getchar();
  }
  if (*w=='\0') {//word was found
      found=1;
      //printf("position=%d\n",position);
      //printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);getchar();
      *b=' ';
      b++;
      strcat(B,new_word);//copy new_word to B[] after word
      //printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);getchar();
      b=b+strlen(new_word);//increment j
      *b=' ';
      a++;b++;
      continue;
  }
  else{//we are here, that means *a!=*w, word dont match...
        *b=*a;//else continue copying A to B
        //printf("A[%d]=%c B[%d]=%c \n",i,A[i],j,B[j]);getchar();
        a++;b++;
        }
}
if(!found) printf("\"%s\" not found!\n",word);
puts(A);
puts(B);
getchar();
 
return 0; 
}

---