If it is possible you should use constant increments instead of multiplies.

#include <stdio.h>

#include <stdlib.h>

int main(void)
{
    int i, j;
    for(i=0; i<10; i++)
    {
        j=i*10;
    }
}

int main1(void)
{
    int i, j;
    for(i=0; i<100; i+=10)

    {
        j=i;
    }
}

For power of two multiplies you can use the shift operator, for example

 

y = x*2 ---> y = x<<1

y = x*4 ---> y = x<<2

y = x*8 ---> y = x<<3

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and naturally you can use the reverse shift operator to perform a divide by a power of two
 

y = x/2 ---> y = x>>1

y = x/4 ---> y = x>>2

y = x/8 ---> y = x>>3

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Gg1