AC

现在做出来了

[========]

[========]

[========]

[========]

扑克牌 第一种解法

#include <bits/stdc++.h>
using namespace std;

int main() {
	int n;
	set<string>s;
	cin >> n;
	string a;
	for (int i = 1; i <= n; i++) {
		cin >> a;
		s.insert(a);
	}
	cout << 52 - s.size();
	return 0;
}

扑克牌-第二种解法

#include <bits/stdc++.h>
using namespace std;
int d[15], c[15], h[15], s[15];

void Insert(char x, char y) {
	int z = 0;
	if (y == 'A')
		z = 1;
	else if (y == 'T')
		z = 10;
	else if (y == 'J')
		z = 11;
	else if (y == 'Q')
		z = 12;
	else if (y == 'K')
		z = 13;
	else
		z = y - '0';
	if (x == 'D')
		d[z]++;
	else if (x == 'C')
		c[z]++;
	else if (x == 'H')
		h[z]++;
	else if (x == 'S')
		s[z]++;
}

int main() {
	int n, ans = 0;
	string a;
	for (int i = 0; i < 15; i++)
		d[i] = c[i] = h[i] = s[i] = 0;
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a;
		Insert(a[0], a[1]);
	}
	for (int i = 1; i <= 13; i++) {
		if (d[i] == 0)
			ans++;
		if (c[i] == 0)
			ans++;
		if (h[i] == 0)
			ans++;
		if (s[i] == 0)
			ans++;
	}
	cout << ans;
	return 0