#include <bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
#pragma GCC optimize("-O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#define fi first
#define se second
#define p_b push_back
#define pll pair<ll,ll>
#define pii pair<int,int>
#define m_p make_pair
#define all(x) x.begin(),x.end()
#define sset ordered_set
#define sqr(x) (x)*(x)
#define pw(x) (1ll << x)
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
const ll MAXN = 1123456;
const ll N = 2e5;
mt19937_64 rnd(chrono::system_clock::now().time_since_epoch().count());
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template <typename T> void vout(T s){cout << s << endl;exit(0);}
int main(){
ios_base :: sync_with_stdio(0);
cin.tie(0);
ll n, k;
cin >> n >> k;
vector <ll> a(n);
set <pll> st;
ll sc = 0, mx = 0;
for(int i = 0; i < n; i++){
cin >> a[i];
st.insert({a[i], i});
sc += a[i];
mx = max(mx, a[i]);
}
if(sc % k)vout(-1);
pll fufel = *--st.end();
st.erase(--st.end());
sc -= mx;
if(sc < mx)vout(-1);
vector < pair<ll, pll> > ans;
while(sc > mx){
pll xe = *--st.end();
st.erase(--st.end());
if(st.empty())vout(-1);
pll xx = *--st.end();
st.erase(--st.end());
xe.fi--;
xx.fi--;
ans.p_b({1ll, {xe.se, xx.se}});
if(xe.fi)st.insert(xe);
if(xx.fi)st.insert(xx);
sc -= 2;
}
while(!st.empty()){
pll xe = *--st.end();
st.erase(--st.end());
ans.p_b({xe.fi, {fufel.se, xe.se}});
}
cout << ans.size() << "\n";
for(auto i : ans)cout << i.fi << " " << i.se.fi + 1 << " " << i.se.se + 1 << "\n";
return 0;
}
