print sequence in order.

print_seq.c

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

void print_seq(int seq[], int len)
{
    int *indices = (int *)malloc(sizeof(int) * (len+1));
    memset(indices, 0, sizeof(int)*(len+1));

    int i;
    for (i = 0; i <= len; ++i) {
        indices[seq[i]] = i;
    }

    int prev_index = 0;

    /* output the first item */
    for (i = 1; i <= len; ++i) {
        if (indices[i] != 0) {
            prev_index = indices[i];
            printf("%d", i);
            break;
        }
    }

    /* output the rest */
    for (i++; i <= len; i++) {
        if (indices[i] < prev_index) {
            printf(", %d", i);
        } else {
            /* new sequence */
            prev_index = indices[i];
            printf("\n%d", i);
        }
    }

    printf("\n");
}

int main(int argc, char *argv[])
{
    int test[] = {1, 2, 5, 8, 10, 4, 3, 6, 9, 7};
    int len = sizeof(test)/sizeof(test[0]);

    print_seq(test, len);

    return 0;
}