关于srand(time(0))的使用方法

Rosalia ·

更新时间:2024-09-20

· 944 次阅读

参考

关于rand()和srand()

问题

起因是想测试一下酒馆战棋十二胖头鱼大乱斗先后手的胜率，测试代码如下：

#include
#include
#include
#define TIMES 1000000
#define PRINT 0
int win, draw, lose;
int score, combat;
int p1cur, p2cur;
int p1rem, p2rem;
int p1sta[6], p2sta[6];
int p1tab[6], p2tab[6];
void battle(bool first);
void battle(int p1no, int p2no);
bool wlcheck();
void printcur();
int main()
{
	win = draw = lose = 0;
	score = combat = 0;
	int t = 0;
	srand(time(0));
	while (t++ < TIMES)
	{
		//千万不要把srand(time(0))写在这里
		p1cur = p2cur = 5;
		p1rem = p2rem = 6;
		for (int i = 0; i < 6; i++)
		{
			p1sta[i] = p2sta[i] = 1;
			p1tab[i] = p2tab[i] = i;
		}
		while (1)
		{
			battle(1);
			if (wlcheck())break;
			printcur();
			battle(0);
			if (wlcheck())break;
			printcur();
		}
	}
	printf("先手胜率：%f%%\n后手胜率：%f%%\n平局率：%f%%\n平均存活随从数：%f\n平均战斗次数：%f\n",
		(double)win * 100 / TIMES,
		(double)lose * 100 / TIMES,
		(double)draw * 100 / TIMES,
		(double)score / TIMES,
		(double)combat / TIMES);
}
void battle(bool first)
{
	if (first)
	{
		do {
			if (p1cur == 5)p1cur = 0; 
			else p1cur++;
		} while (p1sta[p1cur] == -1);
		battle(p1cur, p2tab[rand() % p2rem]);
	}
	else
	{
		do {
			if (p2cur == 5)p2cur = 0;
			else p2cur++;
		} while (p2sta[p2cur] == -1);
		battle(p1tab[rand() % p1rem], p2cur);
	}
}
void battle(int p1no, int p2no)
{
	combat++;
	if (--p1sta[p1no] == -1)
	{
		p1rem--;
		int i = -1;
		while (p1tab[++i] != p1no);
		while (i < p1rem) p1tab[i++] = p1tab[i + 1];
	}
	if (--p2sta[p2no] == -1)
	{
		p2rem--;
		int i = -1;
		while (p2tab[++i] != p2no);
		while (i < p2rem) p2tab[i++] = p2tab[i + 1];
	}
	for (int i = 0; i < 6; i++)
	{
		if (p1sta[i] == 0 && p1no != i)p1sta[i] = 1;
		if (p2sta[i] == 0 && p2no != i)p2sta[i] = 1;
	}
}
bool wlcheck()
{
	if (p1rem == 0 && p2rem == 0)
	{
		draw++; return true;
	}
	else if (p1rem == 0)
	{
		lose++; score -= p2rem; return true;
	}
	else if (p2rem == 0)
	{
		win++; score += p1rem; return true;
	}
	else return false;
}
void printcur()
{
	if (!PRINT)return;
	for (int i = 0; i < 6; i++)
		printf("%d ", p1sta[i]);
	printf("\n");
	for (int i = 0; i < 6; i++)
		printf("%d ", p2sta[i]);
	printf("\n\n");
}

结果

多次运行结果相差不大，后手胜率稍微领先一点点。
在这里插入图片描述