怎么写这道C语言的程序题目.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
//
typedef unsigned int uint;
typedef unsigned short ushort;
static const uint kMaxCount = 256;
//
typedef struct st_ret {
    uint ret[kMaxCount];
    ushort count;
    st_ret* next;
} st_ret;
//
void init_st_ret(st_ret* st)
{
    st->count = 0;
    st->next = 0;
}
//
st_ret* create_st_ret()
{
#ifdef __cplusplus
    st_ret* p = (st_ret*)malloc(sizeof(st_ret));
#else
    st_ret* p = malloc(sizeof(st_ret));
#endif
    init_st_ret(p);
    return p;
}
//
st_ret* fill_st_ret(st_ret* st, uint ret_value)
{
    st_ret* p = st;
    if (st->count >= kMaxCount)
        p = st->next = create_st_ret();
    p->ret[p->count++] = ret_value;
    return p;
}
//
void free_st_ret(st_ret* st_head)
{
    st_ret* p = st_head;
    while (p)
    {
        st_ret* q = p;
        p = p->next;
        free(q);
    }
}
//
void print_st_ret(st_ret* st)
{
    uint i = 0;
    for(; i < st->count; ++i)
        printf("%u\n", st->ret[i]);
}
//
void print_st_rets(st_ret* st_head)
{
    printf("\n");
    st_ret* p = st_head;
    while (p)
    {
        print_st_ret(p);
        p = p->next;
    }
}
//
static const int kMaxNumberLength = 1000;
int trim_big_number(const char* big_number, uint value_upper)
{
    int len = strlen(big_number);
    if (EOF == len || kMaxNumberLength < len)
        return 0;
    int digit_num = 0;
    for (uint i = value_upper; i > 0; ++digit_num, i = i/10) ;
    if (digit_num >= len)
        return strtoul(big_number, NULL, 10);
    else
    {
        const char* trim_number = big_number + len - digit_num;
        return strtoul(trim_number, NULL, 10);
    }
}
//
int main(int argc, char** argv)
{
    st_ret* p = create_st_ret();
    st_ret* q = p;
    char szInputString[1024] = { 0 };
    while (true)
    {
        int a, b, m;
        scanf("%s", szInputString);
        a = trim_big_number(szInputString, 10000);
        scanf("%s", szInputString);
        b = trim_big_number(szInputString, 10000);
        scanf("%d", &m);
        if (a == 0 && b == 0 && m == 0)
            break;
        if (m == 0)
            q = fill_st_ret(q, 0);
        else
            q = fill_st_ret(q, a * b % m);
    }
    print_st_rets(p);
    free_st_ret(p);
    printf("\n");
    system("pause");
    return 0;
}

之前看错题目,以为a, b不大于1000.修改.