This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<bits/stdc++.h>
using namespace std;
const int N = 100'000 +10, K = 51, inf = 1'000'000'000;
int n, k, q, a[N], val[N];
set<int> st[K];
multiset<int> mi;
void process(int x)
{
  int ans = x;
  for(int i = 1; i <= k; i ++)
    if(i != a[x])
      ans = max(ans, *st[i].upper_bound(x));
  
  if(ans < *st[a[x]].upper_bound(x))
    ans = ans - x + 1;
  else
    ans = inf;
  auto it = mi.find(val[x]);
  if(it != mi.end())
    mi.erase(it);
  val[x] = ans;
  mi.insert(val[x]);
}
int main()
{
  ios::sync_with_stdio(false);
  cin.tie(0), cout.tie(0);
  
  cin >> n >> k >> q;
  for(int i = 1; i <= n; i++)
    cin >> a[i];
  
  for(int i = 1; i <= n; i ++)
    st[a[i]].insert(i);
  
  for(int i = 1; i <= k; i++)
    st[i].insert(inf);
  for(int i = 1; i <= n; i ++)
    process(i);
  
		    
  while(q--)
    {
      int t;
      cin >> t;
      if(t == 2)
	{
	  int ans = *mi.begin();
	  cout << (ans > n ? -1 : ans) << "\n";
	}
      else
	{
	  int p, x;
	  cin >> p >> x;
	  st[a[p]].erase(p);
	   a[p] = x;
	  st[a[p]].insert(p);
	  
	  for(int i = 1; i <= k; i ++)
	    {
	      auto it = st[i].upper_bound(p);
	      if(it != st[i].begin())
		{
		  it--;
		  process(*it);
		}
	      if(i == x && it != st[i].begin())
		{
		  it--;
		  process(*it);
		}
	    }
	}
    }
  return 0;
}
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