把高精度的數封裝到一個結構體裡，目前只有加和減

struct HighNum {
	int num[2020];
	bool Fu = 0;
	void Read () {
		std :: string Du;
		std :: getline (std :: cin, Du); 
		for (int i = 1; i <= Du.size (); i ++) {
			num[i] = Du[Du.size () - i] - '0';
		}
		num[0] = Du.size ();
		if (Du[0] == '-') num[num[0]] = 0, num[0] --, Fu = 1;
	}
	void Write () {
		if (Fu) putchar ('-');
		for (int i = num[0]; i >= 1; i --) {
			printf ("%d", num[i]);
		}
	}
	bool operator < (const HighNum& Ri) {
		if (Fu == 1 && Ri.Fu == 0) return 1;
		if (Fu == 0 && Ri.Fu == 1) return 0;
		if (num[0] != Ri.num[0]) return (Fu == 1 && Ri.Fu == 1) ? ! (num[0] < Ri.num[0]) : num[0] < Ri.num[0];
		for (int i = num[0]; i >= 1; i --) {
			if (num[i] != Ri.num[i]) return (Fu == 1 && Ri.Fu == 1) ? ! (num[i] < Ri.num[i]) : num[i] < Ri.num[i];
		}
		return 0;
	}
	bool operator > (const HighNum& Ri) {
		if (Fu == 1 && Ri.Fu == 0) return 0;
		if (Fu == 0 && Ri.Fu == 1) return 1;
		if (num[0] != Ri.num[0]) return (Fu == 1 && Ri.Fu == 1) ? ! (num[0] > Ri.num[0]) : num[0] > Ri.num[0];
		for (int i = num[0]; i >= 1; i --) {
			if (num[i] != Ri.num[i]) return (Fu == 1 && Ri.Fu == 1) ? ! (num[i] > Ri.num[i]) : num[i] > Ri.num[i];
		}
		return 0;
	}
	bool operator <= (const HighNum& Ri) {
		if (Fu == 1 && Ri.Fu == 0) return 1;
		if (Fu == 0 && Ri.Fu == 1) return 0;
		if (num[0] != Ri.num[0]) return (Fu == 1 && Ri.Fu == 1) ? ! (num[0] < Ri.num[0]) : num[0] < Ri.num[0];
		for (int i = num[0]; i >= 1; i --) {
			if (num[i] != Ri.num[i]) return (Fu == 1 && Ri.Fu == 1) ? ! (num[i] < Ri.num[i]) : num[i] < Ri.num[i];
		}
		return 1;
	}
	bool operator >= (const HighNum& Ri) {
		if (Fu == 1 && Ri.Fu == 0) return 0;
		if (Fu == 0 && Ri.Fu == 1) return 1;
		if (num[0] != Ri.num[0]) return (Fu == 1 && Ri.Fu == 1) ? ! (num[0] > Ri.num[0]) : num[0] > Ri.num[0];
		for (int i = num[0]; i >= 1; i --) {
			if (num[i] != Ri.num[i]) return (Fu == 1 && Ri.Fu == 1) ? ! (num[i] > Ri.num[i]) : num[i] > Ri.num[i];
		}
		return 1;
	}
	HighNum operator + (const HighNum& Ri) {
		HighNum To, a, b;
		a = *this; b = Ri;
		for (int i = 1; i <= max (a.num[0], b.num[0]) + 10; i ++) To.num[i] = 0;
		if (a.Fu == 0 && b.Fu == 1) {
			b.Fu = 0;
			To = a - b;
			return To;
		}
		if (a.Fu == 1 && b.Fu == 0) {
			a.Fu = 0;
			To = b - a;
			return To;
		}
		if (a.Fu == 1 && b.Fu == 1) {
			a.Fu = 0; b.Fu = 0;
			To = a + b;
			To.Fu = 1;
			return To;
		}
		To.num[0] = max (a.num[0], b.num[0]) + 1;
		To.num[1] = 0;
		for (int i = 1; i <= To.num[0]; i ++) {
			To.num[i] += a.num[i] + b.num[i];
			To.num[i + 1] = To.num[i] / 10;
			To.num[i] %= 10; 
		}
		if (To.num[To.num[0]] == 0) To.num[0] --;
		return To;
	}
	HighNum operator - (const HighNum& Ri) {
		HighNum To;
		HighNum a, b;
		a = *this;
		b = Ri;
		for (int i = 1; i <= max (a.num[0], b.num[0]) + 10; i ++) To.num[i] = 0;
		if (a.Fu == 0 && b.Fu == 1) {
			b.Fu = 0;
			To = a + b;
			return To;
		}
		if (a.Fu == 1 && b.Fu == 0) {
			a.Fu = 0;
			To = a + b;
			To.Fu = 1;
			return To;
		}
		if (a.Fu == 1 && b.Fu == 1) {
			a.Fu = 0; b.Fu = 0;
			To = b - a;
			return To;
		}
		if (a < b) {
			HighNum SWAP;
			SWAP = a;
			a = b;
			b = SWAP;
			To.Fu = 1;
		}
		To.num[0] = max (this -> num[0], Ri.num[0]);
		for (int i = 1; i <= To.num[0]; i ++) {
			if (a.num[i] < b.num[i]) {
				a.num[i] += 10;
				a.num[i + 1] -= 1;
			}
			To.num[i] = a.num[i] - b.num[i];
		}
		while (To.num[To.num[0]] == 0) To.num[0] --;
		return To;
	}
};