How to Compare elements in arrays

Code:

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I need some help in  finding elements in array "aqq" that matchs with those in "arr"
My code just prints found as zero

  for(i=0;i<count;i++)
  {
    found=0;
    for(j=0;j<k;j++)
    {
      if(strcmp(arr[j],aqq[i])==0)
      {
        found++;
      }
    }
    printf("%s",found);
  }

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strcmp works only with strings and not individual elements of a string.
Assuming that arr[j]and aqq[i] are 2D arrays and not elements of a string.
Take the found=0; outside of the first for loop.
printf("%s",found); /* Isn't found an int. Change to %d */

Code:

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But i need to reset found to =0 but i am comparing using more that one string

say aqq has {and, go, to, the, nowhere}
      arr has {it, to, and, and, and, on, to, the, and, go, go, go}

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It should work if you change the printf() format specifier to %d (assuming found is an int).

Quote:

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Originally Posted by axe

Code:

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But i need to reset found to =0 but i am comparing using more that one string

say aqq has {and, go, to, the, nowhere}
      arr has {it, to, and, and, and, on, to, the, and, go, go, go}

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Code:

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

int main ( void )
{
    char aqq[][8]= { "and", "go", "to", "the", "nowhere"};
    char arr[][4] = {"it", "to", "and", "and", "and", "on", "to", "the", "and", "go", "go", "go"};
    int i, j;
    int first_array = sizeof aqq / sizeof aqq[0];
    int second_array = sizeof arr / sizeof arr[0];
    int results[sizeof aqq / sizeof aqq[0]] = { 0 };
   
    for ( i = 0; i < first_array; i++)
    {
            for ( j = 0; j < second_array; j++ )
            {
                      if ( strcmp(arr[j], aqq[i]) == 0 )
                      {
                        ++results[i];
                      }
            }
            printf( "&#37;s repeats %d times\n", aqq[i], results[i] );
    }
    getchar();   
    return 0;
}

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wow!! sweet!! thanks!!

Would you please explain me the code?

Quote:

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Originally Posted by eXeCuTeR

Would you please explain me the code?

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What part do you not understand?

Basically, the more complicated part:

Code:

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    int first_array = sizeof aqq / sizeof aqq[0];
    int second_array = sizeof arr / sizeof arr[0];
    int results[sizeof aqq / sizeof aqq[0]] = { 0 };
   
    for ( i = 0; i < first_array; i++)
    {
            for ( j = 0; j < second_array; j++ )
            {
                      if ( strcmp(arr[j], aqq[i]) == 0 )
                      {
                        ++results[i];
                      }
            }

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sizeof aqq / sizeof aqq[0] - calculates number of elements inthe array

for ( i = 0; i < first_array; i++) - loops through all elements in the array

strcmp(arr[j], aqq[i]) - compares current string in one array to string in another array

++results[i] - if strings are equall - increases the counter

So what part exactly is hard to understand?

Code:

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strcmp(arr[j], aqq[i]) == 0

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equals to 0? why?

and what does

Code:

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results[sizeof aqq / sizeof aqq[0]] = { 0 };

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do?

thanks so much.

Quote:

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Originally Posted by eXeCuTeR

Code:

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strcmp(arr[j], aqq[i]) == 0

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equals to 0? why?

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It's not saying it equals 0, it is part of an "if" statement and is saying "if it is equal to 0", not "it is equal to 0". The strcmp function returns 0 if the two strings are equal so the whole "if" statement effectively says "if the two strings are equal to each other".

Quote:

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and what does

Code:

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results[sizeof aqq / sizeof aqq[0]] = { 0 };

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do?

thanks so much.

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It was already explained what sizeof aqq / sizeof aqq[0] does. So, combining it with the declaration of the integer array we can say that it creates an integer array of 8 elements (the same number of character pointer elements as aqq contains) called results. It also initializes all the values in that array to 0.

Yeah, I meant that why if it's TRUE it will equal to 0.

Thought it would return 0 if 2 strings are equal at first, guess I was right.

Thanks mate! :D

The reason strcmp() returns 0 for "equal" is that it essentially returns "the a signed difference" - this means that strcmp() can ALSO tell you which if the strings is the greater if they are different. If the return value is > 0, the first string is "greater". If the return value is < 0, the second string is the greater.

So, strcmp("abcd", "abcc") returns something greater than zero, swap the strings around, and you get a negative return. Note that it's not guaranteed what the VALUE itself is, it may be 1 and -1 for all strings, or it may be (commonly is) the difference between the first different letters in the string.

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Mats