index array

hi guys i have this array problem.

say i have an array called index which stores two numbers 1 and 4

i want to scan through an array of say 6 values but i dont want to hit the array[1] and array[4]

how can i do this?

i tried:
assuming index has values 1 and 4, val has two values.

Code:

---

for ( i = 0; i<size-1); i++)
for(j=0;j<val-1;j++)
while(i!=index[j])
for(k=i;k<size-1;k++){
if(foo[i] == bar[k]) {
incre++;
}
}

---

Something like this?

Code:

---

#include <stdio.h>

int main(void)
{
    int i, j, index[] = {1,4}, array[] = {10,20,30,40,50,60};
    for(i = 0; i < sizeof(array)/sizeof(*array); ++i)
    {
        for(j = 0; j < sizeof(index)/sizeof(*index); ++j)
        {
            if(i == index[j])
            {
                goto skip;
            }
        }
        printf("array[%d] = %d\n", i, array[i]);
    skip:
        ;
    }
    return 0;
}

/* my output
array[0] = 10
array[2] = 30
array[3] = 40
array[5] = 60
*/

---

thanks for the reply.

is there any other way i can do this without using that goto statement? im not familiar with that expression. i tried another way below but i still cannot skip the index array.

i tried breaking out of the loop but then i have a problem with the first for loop.
thanks again

Code:

---

void foo_bar( int A[], int B[], int size, int *nx, int *ny )
{
        int i, j, k, n=0, index[SIZE], val=0;

        *ny = 0;
        *nx = 0;

        for ( i=0,j=0; i<=npins-1; i++,j++ ) {
                if ( A[i] == B[j] ) {
                        (*ny)++;
                        val=*ny;
                        index[n]=i;
                        n++;
                }
        }

        for ( i=0; i<=size-1; i++ ) {
                for ( j=0; j<val-1; j++ ) {
                        if ( i == index[j] ) {
                                i++;
                                break;
                        }
                }

                for (k=i; k<=npins-1;k++) {
                        if ( A[i] == B[k] )
                                (*nx)++;
                }
        }

        printf( "%d %d\n", *ny, *nx );
}

---

npins is actually the size

typo..

i have a problem when i run foo_bar2 and it calls foo_bar how come the pointers *nx, *ny never change? it always equals zero when i first initialise it. what have i done wrong? I dont want it to print out the result in foo_bar, i want to pass the pointers in from foo_bar into foo_bar2!

Code:

---


void foo_bar( int A[], int B[], int size, int *nx, int *ny )
{
        int i,j;
        int ctr1 = 0;
        int ctr2 = 0;       
       
        for (i=0;i<size;i++)        {
                if (A[i]==B[i]) {
                ctr1++;
                }
        }
       
                for (j=0;j<size;j++) {
        if ( A[i] != B[j] ) {
        ctr2++;
        }
}
        *nx=ctr1;
        *ny=ctr2;
}


void foo_bar2( int B[], int A[], int size, int *nx, int *ny ) {
        foo_bar( A, B, size, nx, ny );
        printf( "\t%d nx, %d ny\n", *nx, *ny );
        return;
}

---

:confused:

After correcting this one typo (I guess that's what it is):

>>if ( A[i] != B[j] ) {
should be (?)
>>if ( A[j] != B[j] ) {

I use this code:

Code:

---

  int a1[] = {1, 2, 3};
  int a2[] = {1, 2, 3};
  int i = 0, j = 0;
  foo_bar2(a1, a2, 3, &i, &j);

---

And get output:
>> 3 nx, 0 ny

sorry thats not it. this code is just an example of my full program, sort its a little vague.
Im just having problems passing the pointer value into another function, it does not seem to want to accept it.

where i have:

*nx = crt1;
*ny = crt2;

i tried nx=&crt1;
i get weird numbers

i also tried make *nx=0, then i did (*nx)++, so just incrementing the pointer value.

I'm confused, are you trying to increment (or amend) the pointer itself, or the data it points to?

all i basically want to do is have two counters, and i want to assign two pointers, one to each counter, and then pass it forward to a new function.

>is there any other way i can do this without using that goto statement?

I would do it like this.

Code:

---

#include <stdio.h>

int main(void)
{
    int i, j, index[] = {1,4}, array[] = {10,20,30,40,50,60};
    for ( i = 0; i < sizeof(array)/sizeof(*array); ++i )
    {
        for ( j = 0; j < sizeof(index)/sizeof(*index); ++j )
        {
            if ( i == index[j] )
            {
                break;
            }
        }
        if ( j == sizeof(index)/sizeof(*index) )
        {
            printf("array[%d] = %d\n", i, array[i]);
        }
    }
    return 0;
}

---

A functionized version might be like this.

Code:

---

#include <stdio.h>

/*
 * Copy from 'array' to 'result' except for value of 'i' that match any of
 * the values in 'index'.
 */
int foo(const int *array, int asize, const int *index, int isize, int *result)
{
    int i, j, rsize = 0;
    for ( i = 0; i < asize; ++i )
    {
        for ( j = 0; j < isize; ++j )
        {
            if ( i == index[j] )
            {
                break;
            }
        }
        if ( j == isize )
        {
            result[rsize++] = array[i];
        }
    }
    return rsize;
}

/*
 * Print the 'result' array.
 */
void bar(const int *array, int asize, const int *index, int isize, int *result)
{
    int i, rsize = foo(array, asize, index, isize, result);
    for ( i = 0; i < rsize; ++i )
    {
        printf("result[%d] = %d\n", i, result[i]);
    }
}

int main(void)
{
    int index[] = {1,4}, array[] = {10,20,30,40,50,60};
    int result[ sizeof(array)/sizeof(*array) ];
    bar(array, sizeof(array)/sizeof(*array),
        index, sizeof(index)/sizeof(*index),
        result);
    return 0;
}

/* my output
array[0] = 10
array[2] = 30
array[3] = 40
array[5] = 60
*/

---

Going through the other responses, I don't think I quite understand what you want to do (I think I need more caffeine to start my day). So this is here for whatever it may be worth.