【C言語】クイズゲーム作成(8)問題数を増やす

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>

#define	QUIZ_NUM_MAX	10
#define	QUIZ_NUM		5
#define	FLAG_ON			1
#define	FLAG_OFF		0
#define	QUESTION_FILE	"questions.txt"

typedef struct {
	char	mondai[100];
	char	sentaku[3][100];
	int		answer_no;
	int		done_flag;
}quiz_t;

void set_quiz(quiz_t* t, char* m, char* s1, char* s2, char* s3, int a)
{
	strncpy(t->mondai, m, sizeof(t->mondai));
	strncpy(t->sentaku[0], s1, sizeof(t->sentaku[0]));
	strncpy(t->sentaku[1], s2, sizeof(t->sentaku[1]));
	strncpy(t->sentaku[2], s3, sizeof(t->sentaku[2]));
	t->answer_no = a;
	t->done_flag = FLAG_OFF;
}

void change_kaigyou(char* s)
{
	char* p;
	char* w;

	while (1) {
		p = strstr(s, "\\n");
		if (p == NULL) {
			return;
		}
		*p = '\n';
		*p++;
		w = p;
		*w++;
		while (*p++ = *w++);
	}
}

int main(void)
{
	int		ans;
	char	result[QUIZ_NUM][10];
	int		ok_cnt = 0;
	int		i;
	quiz_t	quiz[QUIZ_NUM_MAX];
	int		r;
	FILE* fp;
	int		set_quiz_error_flag = FLAG_OFF;
	char	line[1000];
	char* ptr_mondai;
	char* ptr_sentaku1;
	char* ptr_sentaku2;
	char* ptr_sentaku3;
	char* ptr_answer_no;

	fp = fopen(QUESTION_FILE, "r");
	if (fp == NULL) {
		printf("問題リストのオープンに失敗しました。ファイル名 = %s\n", QUESTION_FILE);
		return -1;
	}

	i = 0;
	while (fgets(line, sizeof(line), fp) != NULL) {
		change_kaigyou(line);
		ptr_mondai = strtok(line, ",");
		if (ptr_mondai == NULL) {
			printf("問題文の登録に失敗しました。ファイル名 = %s, 行数 = %d\n", QUESTION_FILE, i + 1);
			set_quiz_error_flag = FLAG_ON;
			break;
		}

		ptr_sentaku1 = strtok(NULL, ",");
		if (ptr_sentaku1 == NULL) {
			printf("選択肢1の登録に失敗しました。ファイル名 = %s, 行数 = %d\n", QUESTION_FILE, i + 1);
			set_quiz_error_flag = FLAG_ON;
			break;
		}

		ptr_sentaku2 = strtok(NULL, ",");
		if (ptr_sentaku2 == NULL) {
			printf("選択肢2の登録に失敗しました。ファイル名 = %s, 行数 = %d\n", QUESTION_FILE, i + 1);
			set_quiz_error_flag = FLAG_ON;
			break;
		}

		ptr_sentaku3 = strtok(NULL, ",");
		if (ptr_sentaku3 == NULL) {
			printf("選択肢3の登録に失敗しました。ファイル名 = %s, 行数 = %d\n", QUESTION_FILE, i + 1);
			set_quiz_error_flag = FLAG_ON;
			break;
		}

		ptr_answer_no = strtok(NULL, ",");
		if (ptr_answer_no == NULL) {
			printf("正解の登録に失敗しました。ファイル名 = %s, 行数 = %d\n", QUESTION_FILE, i + 1);
			set_quiz_error_flag = FLAG_ON;
			break;
		}

		set_quiz(&quiz[i], ptr_mondai, ptr_sentaku1, ptr_sentaku2, ptr_sentaku3, atoi(ptr_answer_no));
		i++;
	}

	fclose(fp);
	if (set_quiz_error_flag == FLAG_ON) {
		return -1;
	}

	srand((unsigned int)time(NULL));

	i = 0;
	while (i < QUIZ_NUM) {
		r = rand() % QUIZ_NUM_MAX;
		if (quiz[r].done_flag == FLAG_ON) {
			continue;
		}

		printf("[第%d問]\n", i + 1);
		printf("%s\n", quiz[r].mondai);
		printf("1:%s  2:%s  3:%s\n", quiz[r].sentaku[0], quiz[r].sentaku[1], quiz[r].sentaku[2]);
		printf(">>> ");
		scanf("%d", &ans);
		if (ans == quiz[r].answer_no) {
			printf("正解！\n\n");
			strncpy(result[i], "○", sizeof(result[i]));
			ok_cnt++;
		}
		else {
			printf("不正解...\n");
			printf("正解は %d:%s です。\n\n", quiz[r].answer_no, quiz[r].sentaku[quiz[r].answer_no - 1]);
			strncpy(result[i], "×", sizeof(result[i]));
		}

		quiz[r].done_flag = FLAG_ON;
		i++;
	}

	printf("--クイズ終了--\n");
	for (i = 0; i < QUIZ_NUM; i++) {
		printf("[第%d問]...%s\n", i + 1, result[i]);
	}
	printf("あなたは %d 問中 %d 問正解でした (正答率：%d %%)\n", QUIZ_NUM, ok_cnt, (ok_cnt * 100) / QUIZ_NUM);

	return 0;
}

#define	QUIZ_NUM_MAX	10
#define	QUIZ_NUM		5

	quiz_t	quiz[QUIZ_NUM_MAX];

		r = rand() % QUIZ_NUM_MAX;