Language: C++

//#include "pch.h"
#include <iostream>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <bitset>
#include <limits.h>
#include <string>
#include <stack>
#include <deque>
#include <cmath>
#include <bitset>
#include <complex>
#include <functional>
#include <time.h>
#include <stdio.h>

typedef long long ll;
typedef std::pair<int, int> Pii;
typedef std::pair<long long, long long> Pll;
typedef std::pair<double, double> Pdd;

#define rip(i, n, s) for (int i = (s);i < (int)( n ); i++)
#define mapa make_pair
#define all(a) a.begin(), a.end()
#define MM << " " <<

template<typename T>
using MaxHeap = std::priority_queue<T>;
template<typename T>
using MinHeap = std::priority_queue<T, std::vector<T>, std::greater<T>>;

template<typename T>
inline bool chmax(T &a, T b) {
	if (a < b) {
		a = b;
		return true;
	}
	return false;
}
template<typename T>
inline bool chmin(T &a, T b) {
	if (a > b) {
		a = b;
		return true;
	}
	return false;
}
template<typename T>
std::vector<T> vec(int len, T elem) { return std::vector<T>(len, elem); }
template<typename T>
void vdeb(std::vector<T> &da) {
	for (int i = 0;i < da.size();i++) {
		if (i == da.size() - 1) std::cout << da[i];
		else std::cout << da[i] << ' ';
	}
	std::cout << std::endl;
}
template<typename T>
void vdeb(std::vector<std::vector<T>> &da) {
	for (int i = 0;i < da.size();i++) vdeb(da[i]);
	std::cout << std::endl;
}

long long pow(long long n, long long p, long long k) {//n^k(mod p)
	if (!k) return 1;
	long long a = pow(n,p, k>>1);
	a = a * a%p;
	if (k & 1) a = a * n%p;
	return a;
}
void euclid(long long &a, long long &b, long long p) { // a>=b A*b+B*(a-a/b*b)=1
	if (a == 1) {
		a = 1;
	}
	else {
		long long A = b, B = a % b;
		euclid(A, B, p);
		b = (A - (p + a / b) % p * B % p + p) % p;
		a = B;
	}
}
long long rev(long long n, long long p) {//nの逆元 n*x-p*y=1
	//long long q = p;
	//euclid(p, n, p);
	//return n % q;
    return pow(n,p,p-2);
}
long long bino(long long n, long long m, long long p) {//nCm(mod p)
	long long ans = 1, div = 1;
	for(int i = 0;i < m; i++){
		ans = (n - i) * ans % p;
		div = div * (i +1) % p;
	}
	return ans * rev(div, p) % p;
}
struct modint {
	long long num;
	long long p;
	modint() {
		num = 0;
		p = 1000000007;
	}
	modint(int x) {
		p = 1000000007;
		num = (long long)x%p;
	}
	modint(long long x) {
		p = 1000000007;
		num = x % p;
	}
	modint operator+(const modint &other) {
		modint ret;
		ret.p = p;
		ret.num = (num + other.num);
        if(ret.num >= p) ret.num %= p;
		return ret;
	}
	modint operator+(const long long &other) {
		modint ret;
		ret.p = p;
		ret.num = num + (other%p);
        if(ret.num >= p) ret.num %= p;
		return ret;
	}
	modint operator-(const modint &other) {
		modint ret;
		ret.p = p;
		ret.num = (num - other.num + p);
        if(ret.num >= p) ret.num %= p;
		return ret;
	}
	modint operator-(const long long &other) {
		modint ret;
		ret.p = p;
		ret.num = (num - (other%p) + p);
        if(ret.num >= p) ret.num %= p;
		return ret;
	}
	modint operator*(const modint &other) {
		modint ret;
		ret.p = p;
		ret.num = (num*other.num) % p;
		return ret;
	}
	modint operator*(const long long &other) {
		modint ret;
		ret.p = p;
		ret.num = (num*(other%p)) % p;
		return ret;
	}
	modint operator/(const modint &other) {
		modint ret;
		ret.p = p;
		ret.num = (num*rev(other.num, p)) % p;
		return ret;
	}
	modint operator/(const long long &other) {
		modint ret;
		ret.p = p;
		ret.num = (num*rev(other%p, p)) % p;
		return ret;
	}
	void operator+=(const long long &other) {
		num = (num + other) % p;
	}
	void operator+=(const modint &other) {
		num = (num + other.num) % p;
	}
	void operator-=(const long long &other) {
		num = (num - other + p) % p;
	}
	void operator-=(const modint &other) {
		num = (num - other.num + p) % p;
	}
	void operator*=(const long long &other) {
		num = (num*other) % p;
	}
	void operator*=(const modint &other) {
		num = (num*other.num) % p;
	}
};
std::ostream& operator<<(std::ostream &os, const modint &x){
	std::cout << x.num;
	return os;
}

using namespace std;
modint comb(ll a, ll b){
  modint ret(1), div(1);
  rip(i, b, 0){
    ret *= a-i;
    div *= i+1;
  }
  return ret / div;
}

modint X(0);

int main(){
  ll r1, c1, r2, c2;
  cin >> r1 >> c1 >> r2 >> c2;
  modint ans, me, le, ri;
  ri = comb(r1+c1-1, r1-1);
  le = comb(r1+c1-1, c1-1);
  rip(i, r2+c2-r1-c1+1, 0){
    me *= 2;
    me += ri+le;
    ans += me;
    if(c2-c1>i){
      ri *= r1+c1+i;
      ri = ri/(c1+1+i);
    }
    if(c2-c1<=i){
      ri *= r1+c1+i;
      ri = ri/(r1+i+c1-c2);
    }
    if(c2-c1==i){
      ri = X-comb(r1+c2, r1);
    }
    if(r2-r1>i){
      le *= r1+c1+i;
      le = le/(r1+1+i);
    }
    if(r2-r1<=i){
      le *= r1+c1+i;
      le = le/(c1+i+r1-r2);
    }
    //cout << me MM ri MM le<< endl;
    if(r2-r1==i)le = X-comb(c1+r2,c1);
  }
  cout << ans << endl;

Compiler output:
a.cc: In function 'int main()':
a.cc:233:23: error: expected '}' at end of input
  233 |   cout << ans << endl;
      |                       ^
a.cc:201:11: note: to match this '{'
  201 | int main(){
      |           ^