哈哈哈

哈！？

#include <iostream>
#include <vector>
using namespace std;
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
	int n, m;
	cin >> n >> m;
	vector<bool> board(m + 1, false);
	for (int i = 0; i < n; ++i) {
		int ai;
		cin >> ai;
		if (!board[ai]) board[ai] = true;
		else if (ai + 1 <= m && !board[ai + 1]) board[ai + 1] = true; }  
	int count = 0;
	for (bool hasPiece : board) if (hasPiece) ++count; 
	cout << count << endl;
	return 0; }

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