decode.c

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

/* Returns: array of decoded values.  [0] - count of values */
int *decode(char *encoded) {
    int idx = 1;
    int maxlen = 8;
    char *token;
    char *delim = " :;,|";
    int *nums = malloc(maxlen * sizeof(int));

    /* Preserve the original string */
    encoded = strdup(encoded);

    token = strtok(encoded, delim);
    nums[1] = atoi(token);

    while (token = strtok(NULL, delim)) {
        if (idx >= maxlen) {
            maxlen += 8;
            nums = realloc(nums, maxlen * sizeof(int));
        }
        nums[++idx] = atoi(token);
    }

    nums[0] = idx;
    return nums;
}