Non-trivial reverse with offset and limit

non-trivial-reverse.c

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

typedef unsigned char byte_t;


static const byte_t offset =  1;
static const byte_t limit =  4;

static const char in_list[] = {
    'a', 'b', 'c', 
    'd', 'e', 'f', 
    'g', 'i', 'j',
    'k', 'l', 'm', 'n'
};


int main () {

    static const byte_t len =  sizeof(in_list);
    char* out_list = malloc(sizeof(byte_t) * len);

    
    byte_t i = 0;
    
    printf("\noffset = %d;\n\nlimit = %d;\n\n # input (%d)\n\n", offset, limit, len);

    for(i = 0; i != len; ++i)
        printf("\t%d => %c\n", i, in_list[i]);        
    
    /* 
     * wrong reverse output
     */
    
    memset(out_list,0,len);
    
    for (i = offset + limit; i > offset; --i)
        out_list[offset + limit - i]  =  in_list[i - 1];
    
    printf("\n # wrong reverse out (%d) \n\n", limit);
    for(i = 0; i != limit; ++i)
        printf("\t %d => %c\n", i, out_list[i]);    
    
    /* 
     * write reverse output
     */
    
    memset(out_list,0,len);
    
    for (i = offset; i < offset + limit; ++i) 
        out_list[i - offset]  =  in_list[len - i - 1];
    
    printf("\n # reverse out (%d) \n\n", limit);
    for(i = 0; i != limit; ++i)
        printf("\t %d => %c\n", i, out_list[i]);        
    
    /* 
     * write direct output
     */
    
    memset(out_list,0,len);
    
    for (i = offset; i < offset + limit; ++i)  
        out_list[i - offset]  =  in_list[i];
        
    printf("\n # direct out (%d) \n\n", limit);
    for(i = 0; i != limit; ++i)
        printf("\t %d => %c\n", i, out_list[i]);        
    
    printf("\n");
    
    return 0;
}

with

• offset = 1;
• limit = 4;

input (13)

    0 => a
    1 => b
    2 => c
    3 => d
    4 => e
    5 => f
    6 => g
    7 => i
    8 => j
    9 => k
    10 => l
    11 => m
    12 => n

wrong reverse out (4)

     0 => e
     1 => d
     2 => c
     3 => b

reverse out (4)

     0 => m
     1 => l
     2 => k
     3 => j

direct out (4)

     0 => b
     1 => c
     2 => d
     3 => e

`