CareerCup

void memcpy( void *pDst, void *pSrc, int len )
{
int i;

if( pDst == NULL || pSrc == NULL )
return;

for( i=0; i<len; i++ )
{
((unsigned char*)pDst)[i] = ((unsigned char*)pSrc)[i];
}
}

char* memcpy(char arr2[], char arr1[], arr1Len) { //char can be replaced by any other datatype
    int i = 0;
    for (i = 0; i < arr1Len+1; i++) {
        arr2[i] = arr1[i];
    }
    return(arr2);
}

You haven't taken care for the memory overlap case guys. What if pSrc < pDst+len?

void memcpy(void *dst, void *src, size_t len)
{
// if(!dst||!src) ... ; not sure if this is needed.
char* dst_c = (char*)dst;
char* src_c = (char*)src;
while(len--) {*dst++=*src++;}
}

void * memcpy(void * dst, void * src, size_t count)
;       {
;               void * ret = dst;
;
;               if (dst <= src || dst >= (src + count)) {
;                       /*
;                        * Non-Overlapping Buffers
;                        * copy from lower addresses to higher addresses
;                        */
;                       while (count--)
;                               *dst++ = *src++;
;                       }
;               else {
;                       /*
;                        * Overlapping Buffers
;                        * copy from higher addresses to lower addresses
;                        */
;                       dst += count - 1;
;                       src += count - 1;
;
;                       while (count--)
;                               *dst-- = *src--;
;                       }
;
;               return(ret);
;       }