Go: package main

import "fmt"

func abs(a int) int {
	if a >= 0 {
		return a
	}
	return -a
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func main() {
	var a, b, c, d int
	fmt.Scan(&a, &b, &c, &d)
	ans := 10000
	ans = min(ans, abs((a+b)-(c+d)))
	ans = min(ans, abs((a+c)-(b+d)))
	ans = min(ans, abs((a+d)-(b+c)))
	fmt.Println(ans)
}

C++: #include<iostream>
#include<vector>
#include<string>
#define rep(i, start, end) for (int i = (int)start; i < (int)end; ++i)
#define rrep(i, start, end) for (int i = (int)start - 1; i >= (int)end; --i)
#define all(x) (x).begin(), (x).end()
using namespace std;
using ll = long long;
template<typename T> inline bool chmax(T& a, T b) {if (a < b) {a = b; return true;} return 0;}
template<typename T> inline bool chmin(T& a, T b) {if (a > b) {a = b; return true;} return 0;}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    vector<int> rate(4);
    for (auto& r : rate) {
        cin >> r;
    }
    int ans = 1 << 30;
    rep(mask, 0, 1 << 4) {
        if (__builtin_popcount(mask) != 2) {
            continue;
        }
        int team1 = 0, team2 = 0;
        rep(i, 0, 4) {
            if ((mask >> i) & 1) {
                team1 += rate[i];
            }
            else {
                team2 += rate[i];
            }
        }
        chmin(ans, abs(team1 - team2));
    }
    cout << ans << endl;
    return 0;
}

C++: #include <algorithm>
#include <array>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <vector>
using namespace std;
#define int long long
constexpr int INF = 1000000000 + 8;

signed main() {
    cin.tie(0);
    ios::sync_with_stdio(0);

    int a, b, c, d;
    cin >> a >> b >> c >> d;

    int ans = INF;
    ans = min(abs(a + b - c - d), ans);
    ans = min(abs(a + c - b - d), ans);
    ans = min(abs(a + d - b - c), ans);

    cout << ans << endl;
}

C++: // warm heart, wagging tail,and a smile just for you!
//                                                                     ███████████
//                                                                   ███╬╬╬╬╬╬╬╬╬╬███
//                                                                ███╬╬╬╬╬████╬╬╬╬╬╬███
//                                            ███████████       ██╬╬╬╬╬████╬╬████╬╬╬╬╬██
//                                      █████████╬╬╬╬╬████████████╬╬╬╬╬██╬╬╬╬╬╬███╬╬╬╬╬██
//                               ████████╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬█████████╬╬╬╬╬╬██╬╬╬╬╬╬╬██
//                             ████╬██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬█████████╬╬╬╬╬╬╬╬╬╬╬██
//                           ███╬╬╬█╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██╬╬███╬╬╬╬╬╬╬█████
//                         ███╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██╬╬╬████████╬╬╬╬╬██
//                       ███╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬███╬╬╬╬╬╬╬╬╬███
//                     ███╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬█████╬╬╬╬╬╬╬██
//                 ████╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬████╬╬╬╬╬████
//     █████████████╬╬╬╬╬╬╬╬██╬╬╬╬╬████╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬█████╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬███╬╬╬╬██████
//   ████╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██╬╬██████╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██████╬╬╬╬╬╬╬███████████╬╬╬╬╬╬╬╬██╬╬╬██╬╬╬██
// ███╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬████╬╬╬╬╬╬╬╬╬╬╬█╬╬╬╬╬╬╬██╬╬╬╬╬╬╬╬██
// ██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██╬╬╬╬▓▓▓▓▓▓╬╬╬████╬╬████╬╬╬╬╬╬╬▓▓▓▓▓▓▓▓██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██╬╬╬╬╬╬╬███
// ██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██████▓▓▓▓▓▓▓╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬▓▓▓▓▓▓▓██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██╬╬╬╬█████
// ███╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬███╬╬╬╬╬██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬█████╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬████████
//   ███╬╬╬╬╬╬╬╬╬╬╬╬╬█████╬╬╬╬╬╬╬╬██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬███╬╬██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬██
//       ██████████████  ████╬╬╬╬╬╬███████████████████████████╬╬╬╬╬██╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬╬████
//                         ███████                           █████  ███████████████████  
//
#include "bits/stdc++.h"
using namespace std;
#define INF (1<<30)
#define LINF (1LL<<60)
#define fs first
#define sc second
#define int long long
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define RFOR(i,a,b) for(int i = (b-1);i>=(a);--i)
#define REP(i,n)  FOR(i,0,(n))
#define RREP(i,n) RFOR(i,0,(n))
#define ITR(itr,mp) for(auto itr = (mp).begin(); itr != (mp).end(); ++itr)
#define RITR(itr,mp) for(auto itr = (mp).rbegin(); itr != (mp).rend(); ++itr)
#define range(i,a,b) ((a)<=(i) && (i)<(b))
#define debug(x)  cout << #x << " = " << (x) << endl
#define SP << " " << 
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}
#define MSB(x) (63-__builtin_clzll(x))
#define pcnt(x) (__builtin_popcountll(x))
#define parity(i,j) (i&(1LL<<j))
typedef pair<int,int> P;
typedef tuple<int,int,int> T;
typedef vector<int> vec;
typedef vector<vector<int>> mat;

signed main(){
  ios::sync_with_stdio(false);
  cin.tie(0);

  vector<int> a(4);
  REP(i,4) cin >> a[i];
  
  sort(a.begin(),a.end());

  int ans = INF;
  do{
    int now = a[0]+a[1]-a[2]-a[3];
    chmin(ans,abs(now));
  }while(next_permutation(a.begin(),a.end()));

  cout << ans << endl;

  return 0;
}

C++: #include <iostream>
#include <cmath>
#include <numeric>
#include <algorithm>
#include <deque>
#include <vector>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <map>
#include <stack>
#include <queue>
#include <functional>
#include <climits>
#include <bitset>
#include <random>
#include <tuple>
#include <initializer_list>
#include <fstream>

int main() {
	std::vector<int> team(4); for (auto& t : team) std::cin >> t;
	std::sort(team.begin(), team.end());
	std::cout << std::abs(team[0] + team[3] - team[1] - team[2]) << std::endl;
}

C++: #include<bits/stdc++.h>
using namespace std;
typedef long long ll;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
const ll INF=1LL<<60;
int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int a,b,c,d;cin >> a >> b >> c >> d;
    cout << min({abs(a+b-(c+d)),abs(a+c-(b+d)),abs(a+d-(c+b))}) << endl;
}

C++: #include <bits/stdc++.h>
using namespace std;
const long long INF = 1LL<<60;
#define REP(i,n) for(int i=0;i<n;i++)
#define REP2(i,m,n) for(int i=m;i<n;i++)
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
int main(){
    int rate[4];
    REP(i,4){
        cin >> rate[i];
    }
    sort(rate,rate+4);

    cout << abs(rate[3]+rate[0] -rate[2]-rate[1])<<endl;

}

C++: #include <bits/stdc++.h>

using namespace std;
using namespace std::string_literals;
using ll = int64_t;
using vecint = vector<int>;
using vecll = vector<ll>;

int main() {
  vecint v(4);
  for(auto&& e:v) cin>>e;
  sort(begin(v),end(v));
  int x=v[0]+v[3];
  int y=v[1]+v[2];
  cout<<abs(x-y)<<endl;

  return 0;
}

C++: #include<iostream>
#include<vector>
#include<string>
#include<algorithm>
#define rep(i,n) for(int i = 0; i < n; ++i)
using namespace std;
using Int = long long;

int main(){
    vector<int>v(4);
    for(auto& e : v) cin >> e;
    int ans = 1e9;
    sort(v.begin(),v.end());
    do{
        ans = min(ans,abs((v[0] + v[1]) - (v[2] + v[3])));
    }while(next_permutation(v.begin(), v.end()));
    cout << ans << endl;
}