缺省源

• fread 快读

namespace IO
{
	char buf[1 << 20], *pa = buf, *pb = buf;
	#define Gc() (pa == pb && (pb = (pa = buf) + fread(buf, 1, 1 << 20, stdin), pa==pb) ? EOF : *pa++)
	inline int Read()
	{
		int x = 0, f = 1;
		char c = Gc();
		while (c < '0' || c > '9')
		{
			if (c == '-')
				f = -1;
			c = Gc();
		}
		while (c >= '0' && c <= '9')
			x = (x << 1) + (x << 3) + (c ^ 48), c = Gc();
		return x * f;
	}
	static int sta[35];
	void Write(int x)
	{
		int top = 0;
		do
		{
			sta[top++] = x % 10;
			x /= 10;
		}while (x);
		while (top)
			putchar(sta[--top] + '0');
	}
	void Write(int x, char ch)
	{
		Write(x);
		putchar(ch);
	}
}

• define 大军

#include <bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define ld long double
#define lll __int128
#define pii pair<int, int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define U(l, r, i) for (int i = l; i <= r; i++)
#define D(l, r, i) for (int i = l; i >= r; i--)