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STRCMP pointer problem

Posted on 2003-10-24
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Last Modified: 2008-02-26
Greetings everyone,

I am comparing elements of two pointer char arrays and comparing them using the string function strcmp. Both arrays contain words, one word at each element. My objective is to find out if there is any word present in the first array which matches the list of words in the 2nd. s1 is the first pointer array, s2 is the second.

for(i=0;i<length_of_ptr1;i++)
     {
          for(j=0;j<length_of_ptr2;j++)
          {    
               if(strcmp(s1[i],s2[j])==0)
               {
                    //printf("s1=%s s2=%s",s1,s2);
                    Counter++;
               }
          }
     }

The above code gives me a memory error when I run it( MS Visual C++ IDE). When I change to code to this,

char *a,*b;
for(i=0;i<length_of_ptr1;i++)
     {
                     a=s1[i];
          for(j=0;j<length_of_ptr2;j++)
          {  b=s2[j];    
               if(strcmp(a,b)==0)
               {
                                        Counter++;
               }
          }
     }

This also gives me a memory error. When I change the above code to if(strcmp(&a,&b)==0)
instead of if(strcmp(a,b)==0), it doesnt give me an error but the counter value is equal to the number of words in the 2nd array. What is going wrong? TIA.

PS- I have dynamically allocated memory to all pointers and pointer arrays. No problem there.
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Question by:Gambit2025
2 Comments
 
LVL 6

Accepted Solution

by:
GaryFx earned 250 total points
ID: 9614562
Assuming you're running this in debug mode, you ought to be able to identify exactly which line prompts the memory error, and what the values of s1[i] and s2[j] are at that time.

If you need more help, please post the code where you declare and build s1 and s2.  The fact that the allocation of the arrays doesn't produce a run time exception doesn't prove there are no problems there.

Gary
0
 

Author Comment

by:Gambit2025
ID: 9614595
I got it now. Problem solved. Debugging helped. Thanks GaryFx.
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