C言語で書いてみました

■ 数当てゲーム（平成14年午後2問1）

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

/* 平成14年午後2 */
#define N   5040
#define M   255

int log[M], guess[M][10], nums[N], index;

int set_answer()
{
    int tab[10], n, i, a;
    for (i = 0; i < 10; i++) tab[i] = 0;
    n = 0;
    for (i = 1; i <= 4; i++) {
        do {
            a = rand() % 10;
        } while (tab[a] != 0);
        tab[a] = 1;
        n = n * 10 + a;
    } 
    return n;
} 

void make_pos(int y, int pos[])
{
    int i, m; 
    for (i = 0; i < 10; i++)
        pos[i] = 0; 
    for (i = 1; i <= 4; i++) {
        m = y % 10;
        y /= 10; 
        pos[m] = i;
    } 
}

int sim(int x, int pos[])
{ 
    int hit, miss, i, p;
    hit = 0;
    miss = 0;
    for (i = 1; i <= 4; i++) {
        p = x % 10;
        x /= 10;
        if (pos[p] != 0) {
            if (pos[p] == i) hit++;
            else miss++;
        }
    }
    return hit * 10 + miss;
} 

int make_guess(int k)
{
    int j;
    index++;
    for (;;) {
        j = 0;
        while (j < k-1 && sim(nums[index], guess[j]) == log[j])
            j++; 
        if (j < k-1) {
            index++;
            if (index >= N) index = 0;
        } else {
            return nums[index];
        }
    }
    return -1;
}

void play()
{
    int ans, pos_a[10], i, r, g, hit, miss, guess_person;
    ans = set_answer();
    make_pos(ans, pos_a);
    index = -1;
    i = 1;
    for (;;) {
        rewind(stdin);
        scanf("%d", &guess_person);
        r = sim(guess_person, pos_a);
        printf("%d %d\n", r / 10, r % 10);
        g = make_guess(i);
        printf("%04d\n", g);
        rewind(stdin);
        scanf("%d %d", &hit, &miss);
        if (hit == 4 || r == 40)
            break;
        log[i-1] = 10 * hit + miss;
        make_pos(g, guess[i-1]);
        i++;
    }
    if (hit != 4)
        printf("あなたの勝ちです\n");
    else if (r != 40)
        printf("私の勝ちです\n");
    else
        printf("引き分けです\n");
}

void init()
{
    int i, j, k, m, p = 0, n[3], t, a, b;
    for (i = 0; i <= 9; i++) {
        n[0] = i;
        for (j = 0; j <= 9; j++) {
            if (n[0] != j) {
                n[1] = j;
                for (k = 0; k <= 9; k++) {
                    if (n[0] != k && n[1] != k) {
                        n[2] = k;
                        for (m = 0; m <= 9; m++) {
                            if (n[0] != m && n[1] != m && n[2] != m) {
                                nums[p++] = n[0] * 1000 + n[1] * 100 + n[2] * 10 + m;
                            }
                        }
                    }
                }
            }
        }
    }
    while (j-- > 0) {
        a = rand() % N;
        b = rand() % N;
        t = nums[a];
        nums[a] = nums[b];
        nums[b] = t;
    }
}

int main()
{
    char r; 
    srand(time(NULL));
    init();
    for (;;) {
        play(); 
        printf("ゲームを続けますか?　Y/N");
        rewind(stdin);
        scanf("%c", &r);
        if (r == 'N')
            return 0;
    }
    return 0;
}