1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
/* Dejwo to ziomal ®© */

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector <int> vi;
typedef vector <ll> vl;
typedef pair <int, int> pi;
typedef pair <ll, ll> pl;
typedef tuple <int, int, int> ti;
typedef vector < pl > vpl;
typedef vector < pi > vpi;
typedef vector < ti > vti;

//double t = clock();
//cout << (clock() - t) / CLOCKS_PER_SEC <<endl;
bool debug = false;
#define deb if(debug)
#define pb push_back
#define FOR(i,x,n) for(int i = x; i < n; i++)
#define SIZE (3 * 1e5 + 42)
#define MAX (1000000 + 42)
#define MOD (1000000000 + 9)
#define DRZ (2<<21)
#define PI 3.14159265

int solve()
{
  int n, m;
  cin >> n >> m;
  int M[ n ][ n ], H[ n ][ n ];
  FOR(i, 0, n)
    FOR(j, 0, n)
      M[ i ][ j ] = (i - j + 1) * (j + 1);

  int ans = INT_MAX;
  FOR(i, 0, n)
  {
    FOR(j, 0, i + 1)
    {
      cin >> H[ i ][ j ];
      if(M[ i ][ j ] <= m)
        ans = min(ans, H[ i ][ j ]);
    }
  }

  return ans;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    FOR(i, 0, 1)
    {
      cout << solve() << endl;
    }

    return 0;
}