Language: C++

#include "bits/stdc++.h"
#include<unordered_map>
#include<unordered_set>
#pragma warning(disable:4996)
using namespace std;
using ld = long double;
template<class T>
using Table = vector<vector<T>>;
const ld eps=1e-9;

// < "D:\D_Download\Visual Studio 2015\Projects\programing_contest_c++\Debug\a.txt" > "D:\D_Download\Visual Studio 2015\Projects\programing_contest_c++\Debug\b.answer"



const int mod = 1000000007;
struct Mod {
public:
	int num;
	Mod() : Mod(0) { ; }
	Mod(long long int n) : num((n % mod + mod) % mod) {
		static_assert(mod<INT_MAX / 2, "mod is too big, please make num 'long long int' from 'int'");
	}
	Mod(int n) : Mod(static_cast<long long int>(n)) { ; }
	operator int() { return num; }
};

Mod operator+(const Mod a, const Mod b) { return Mod((a.num + b.num) % mod); }
Mod operator+(const long long int a, const Mod b) { return Mod(a) + b; }
Mod operator+(const Mod a, const long long int  b) { return b + a; }
Mod operator++(Mod &a) { return a + Mod(1); }
Mod operator-(const Mod a, const Mod b) { return Mod((mod + a.num - b.num) % mod); }
Mod operator-(const long long int a, const Mod b) { return Mod(a) - b; }
Mod operator--(Mod &a) { return a - Mod(1); }
Mod operator*(const Mod a, const Mod b) { return Mod(((long long)a.num * b.num) % mod); }
Mod operator*(const long long int a, const Mod b) { return Mod(a)*b; }
Mod operator*(const Mod a, const long long int b) { return Mod(b)*a; }
Mod operator*(const Mod a, const int b) { return Mod(b)*a; }
Mod operator+=(Mod &a, const Mod b) { return a = a + b; }
Mod operator+=(long long int &a, const Mod b) { return a = a + b; }
Mod operator-=(Mod &a, const Mod b) { return a = a - b; }
Mod operator-=(long long int &a, const Mod b) { return a = a - b; }
Mod operator*=(Mod &a, const Mod b) { return a = a * b; }
Mod operator*=(long long int &a, const Mod b) { return a = a * b; }
Mod operator*=(Mod& a, const long long int &b) { return a = a * b; }
Mod operator^(const Mod a, const int n) {
	if (n == 0) return Mod(1);
	Mod res = (a * a) ^ (n / 2);
	if (n % 2) res = res * a;
	return res;
}
Mod mod_pow(const Mod a, const int n) {
	if (n == 0) return Mod(1);
	Mod res = mod_pow((a * a), (n / 2));
	if (n % 2) res = res * a;
	return res;
}
Mod inv(const Mod a) { return a ^ (mod - 2); }
Mod operator/(const Mod a, const Mod b) {
	assert(b.num != 0);
	return a * inv(b);
}
Mod operator/(const long long int a, const Mod b) {
	return Mod(a) / b;
}
Mod operator/=(Mod &a, const Mod b) {
	return a = a / b;
}

#define MAX_MOD_N 1024000

Mod fact[MAX_MOD_N], factinv[MAX_MOD_N];
void init(const int amax = MAX_MOD_N) {
	fact[0] = Mod(1); factinv[0] = 1;
	for (int i = 0; i < amax - 1; ++i) {
		fact[i + 1] = fact[i] * Mod(i + 1);
		factinv[i + 1] = factinv[i] / Mod(i + 1);
	}
}
Mod comb(const int a, const int b) {
	return fact[a] * factinv[b] * factinv[a - b];
}

string st;
int a;
pair<int, int>getexpr();
pair<int, int>getval() {
	assert(st[a] == 'x');
	a++;
	int num = 0;
	while (a!=st.size()&&isdigit(st[a])) {
		num = num * 10 + st[a] - '0';
		a++;
	}
	return make_pair(1, 1);
}
pair<int, int>getfact() {
	if (st[a] == '~') {
		a++;
		auto p = getfact();
		return make_pair(p.second, p.first);
	}
	else if (st[a] == '(') {
		a++;
		auto p(getexpr());
		a++;
		return p;
	}
	else {
		auto p(getval());
		return p;
	}
}
pair<int, int>getterm() {
	auto p=getfact();
	while (a != st.size()) {
		if (st[a] == '|'||st[a]==')')return p;
		else if (st[a] == '&') {
			a++;
			long long 	int aa = p.first, ab = p.second, ba = q.first, bb = q.second;
			long long int fst = ba*aa;
			long long int scd =  (aa + ab)*(ba + bb) - ba*aa;

			p = make_pair(fst%mod, scd%mod);
		}
	}
	return p;
}
pair<int, int> getexpr() {
	auto p(getterm());
	while (a != st.size()) {
		if (st[a] == '|') {
			a++;
			auto q = getterm();
			long long 	int aa = p.first, ab = p.second, ba = q.first, bb = q.second;
			long long int fst = (aa + ab)*(ba + bb) - bb*ab;
			long long int scd = bb*ab;
			p = make_pair(fst%mod, scd%mod);
		}
		else if(st[a]==')'){
			break;
		}
		else {
			break;
			assert(false);
		}
	}
	return p;
}
long long int eord, enew;
int main() {
	const int SZ = 128 * 1024 * 1024;
	void *p = malloc(SZ);
	enew = (long long)p + SZ - 1;

	__asm__("mov %rsp, eord");
	__asm__("mov enew, %rsp");

	cin >> st;
	a = 0;
	int ans = getexpr().first;
	cout << ans << endl;
	__asm__("mov eord, %rsp");
	return 0;
}

Compiler output:
a.cc: In function 'std::pair<int, int> getterm()':
a.cc:119:79: error: 'q' was not declared in this scope
  119 |                         long long       int aa = p.first, ab = p.second, ba = q.first, bb = q.second;
      |                                                                               ^
a.cc:121:62: error: 'bb' was not declared in this scope; did you mean 'ba'?
  121 |                         long long int scd =  (aa + ab)*(ba + bb) - ba*aa;
      |                                                              ^~
      |                                                              ba