public override bool Equals(object obj)
{
Quadraplet o = (Quadraplet)obj;
bool ans = o.a == a && o.b == b && o.c == c && o.d == d;
return(ans);
}
public override bool Equals(object obj)
{
Quadraplet o = (Quadraplet)obj;
bool ans = this.a == o.a && this.b == o.b && this.c == o.c && this.d == o.d;
return(ans);
}
public static List <IList <int> > FourSum(int[] nums, int target)
{
Dictionary <int, List <couple> > hm = new Dictionary <int, List <couple> >();
for (int i = 0; i < nums.Length - 1; i++)
{
for (int j = i + 1; j < nums.Length; j++)
{
int sum = nums[i] + nums[j];
if (!hm.ContainsKey(sum))
{
List <couple> l = new List <couple>();
l.Add(new couple(i, j));
hm.Add(sum, l);
}
else
{
hm[sum].Add(new couple(i, j));
}
}
}
HashSet <Quadraplet> qset = new HashSet <Quadraplet>();
//IEnumerator en_hm = hm.Keys.GetEnumerator();
//while (en_hm.MoveNext())
foreach (int key in hm.Keys)
{
// int currentsum = (int)en_hm.Current;
int currentsum = key;
int needed = target - currentsum;
if (!hm.ContainsKey(needed))
{
continue;
}
List <couple> curentsumList = hm[currentsum];
List <couple> targetsumList = hm[needed];
foreach (couple currentListCouple in curentsumList)
{
foreach (couple targetListCouple in targetsumList)
{
if (currentListCouple.Equals(targetListCouple))
{
continue;
}
Quadraplet q = new Quadraplet(nums[currentListCouple.i], nums[currentListCouple.j], nums[targetListCouple.i], nums[targetListCouple.j]);
if (qset.Contains(q))
{
continue;
}
qset.Add(q);;
}
}
}
var ans = qset.Select(x => new List <int>
{
x.a,
x.b,
x.c,
x.d
}).ToList();
List <IList <int> > ans2 = new List <IList <int> >();
foreach (Quadraplet eachQuadraplet in qset)
{
List <int> singlelist = new List <int>();
singlelist.Add(eachQuadraplet.a);
singlelist.Add(eachQuadraplet.b);
singlelist.Add(eachQuadraplet.c);
singlelist.Add(eachQuadraplet.d);
ans2.Add(singlelist);
}
return(ans2);
}
public static List <List <int> > FourSum(int[] nums, int target)
{
HashSet <Quadraplet> allQuadraplets = new HashSet <Quadraplet>();
for (int i = 0; i < nums.Length - 3; i++)
{
for (int j = i + 1; j < nums.Length - 2; j++)
{
for (int k = j + 1; k < nums.Length - 1; k++)
{
for (int l = k + 1; l < nums.Length; l++)
{
if (nums[i] + nums[j] + nums[k] + nums[l] == target)
{
Quadraplet obj = new Quadraplet(nums[i], nums[j], nums[k], nums[l]);
if (!allQuadraplets.Contains(obj))
{
allQuadraplets.Add(obj);
}
}
}
}
}
}
List <IList <int> > ans = new List <IList <int> >();
foreach (Quadraplet eachQuadraplet in allQuadraplets)
{
List <int> singlelist = new List <int>();
singlelist.Add(eachQuadraplet.a);
singlelist.Add(eachQuadraplet.b);
singlelist.Add(eachQuadraplet.c);
singlelist.Add(eachQuadraplet.d);
ans.Add(singlelist);
}
var ss =
allQuadraplets.Select(x => new List <int>
{
x.a,
x.b,
x.c,
x.d
}).ToList();
//foreach (IList<int> i in ans)
//{
// foreach (int k in i)
// {
// Console.WriteLine(k);
// }
//}
return(ss);
}