Language: C++

#include<bits/stdc++.h>
using namespace std;
long long a[200005]；
long long n, t1, t2, t3, ans;
long long cal(long long x, long long y, long long z)
{
	long long aaa=a[x],bbb=a[y]-a[x],ccc=a[z]-a[y],ddd=a[N]-a[z];
	return abs(max(max(aaa, bbb), max(ccc, ddd))-min(min(aaa, bbb), min(ccc, ddd)));
}
int main()
{
	scanf("%lld", &n);
	for(register int i=1;i<=n;++i){
		scanf("%lld", a[i]);
		a[i]+=a[i-1];
	}
	t1=1;t2=2;t3=3;
	ans=cal(t1,t2,t3);
	for( ; t2<=n-2; ++t2)
	{
		while(t1+1 < t2&&abs(a[t2]-2*a[t1+1]) < abs(a[t2]-2*a[t1]))++t1;
		while(t3+1 < n&&abs(a[n]-2*a[t3+1]+a[t2]) < abs(a[n]-2*a[t3]+a[t2]))++t3;
		ans=min(ans, cal(t1, t2, t3));
	}printf("%lld\n",ans);
	return 0;
}

Compiler output:
a.cc:3:20: error: expected initializer before '\U0000ff1b'
    3 | long long a[200005]；
      |                    ^~
a.cc: In function 'long long int cal(long long int, long long int, long long int)':
a.cc:7:23: error: 'a' was not declared in this scope
    7 |         long long aaa=a[x],bbb=a[y]-a[x],ccc=a[z]-a[y],ddd=a[N]-a[z];
      |                       ^
a.cc:8:33: error: 'bbb' was not declared in this scope
    8 |         return abs(max(max(aaa, bbb), max(ccc, ddd))-min(min(aaa, bbb), min(ccc, ddd)));
      |                                 ^~~
a.cc:8:43: error: 'ccc' was not declared in this scope
    8 |         return abs(max(max(aaa, bbb), max(ccc, ddd))-min(min(aaa, bbb), min(ccc, ddd)));
      |                                           ^~~
a.cc:8:48: error: 'ddd' was not declared in this scope
    8 |         return abs(max(max(aaa, bbb), max(ccc, ddd))-min(min(aaa, bbb), min(ccc, ddd)));
      |                                                ^~~
a.cc: In function 'int main()':
a.cc:12:24: error: 'n' was not declared in this scope; did you mean 'yn'?
   12 |         scanf("%lld", &n);
      |                        ^
      |                        yn
a.cc:13:26: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   13 |         for(register int i=1;i<=n;++i){
      |                          ^
a.cc:14:31: error: 'a' was not declared in this scope
   14 |                 scanf("%lld", a[i]);
      |                               ^
a.cc:17:9: error: 't1' was not declared in this scope; did you mean 'y1'?
   17 |         t1=1;t2=2;t3=3;
      |         ^~
      |         y1
a.cc:17:14: error: 't2' was not declared in this scope; did you mean 'tm'?
   17 |         t1=1;t2=2;t3=3;
      |              ^~
      |              tm
a.cc:17:19: error: 't3' was not declared in this scope; did you mean 'tm'?
   17 |         t1=1;t2=2;t3=3;
      |                   ^~
      |                   tm
a.cc:18:9: error: 'ans' was not declared in this scope; did you mean 'abs'?
   18 |         ans=cal(t1,t2,t3);
      |         ^~~
      |         abs
a.cc:21:38: error: 'a' was not declared in this scope
   21 |                 while(t1+1 < t2&&abs(a[t2]-2*a[t1+1]) < abs(a[t2]-2*a[t1]))++t1;
      |                                      ^
a.cc:22:37: error: 'a' was not declared in this scope
   22 |                 while(t3+1 < n&&abs(a[n]-2*a[t3+1]+a[t2]) < abs(a[n]-2*a[t3]+a[t2]))++t3;
      |                                     ^