#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vi> vvi;
typedef vector<vll> vvll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define run int teodorfonburgjenasgospodar; cin >> teodorfonburgjenasgospodar; while (teodorfonburgjenasgospodar--)
#define f first
#define s second
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define pb push_back
#define yes cout << "YES\n";
#define no cout << "NO\n";
#define cintienull ios_base::sync_with_stdio(0); cin.tie(0);
#define mp make_pair
#define inputV(a, n) for(int i = 0; i < n; i++)cin>>a[i];
#define ov(a, n) for(int i = 0; i < n; i++)cout << a[i] << " ";
#define ovr(a, n) for(int i = 0; i < n; i++)cout << a[i] << "\n";
#define INF 1000000000
#define LINF 1000000000000000000LL
#define EPS 1e-9
#define MOD 1000000007;


int main()
{
    cintienull
    int n,l;
    cin >> n >> l;
    for (int i = 1; i <= n; i++) {
        int h; cin >> h;
        if(h <= l){
            cout << i;
            return 0;
        }
    }
    cout << -1;
    return 0;
}