#include "triples.h"
#include <bits/stdc++.h>
using namespace std;
#define _ << ' ' <<
using ll = long long;
long long count_triples(std::vector<int> H) {
vector<ll> a(H.begin(), H.end());
ll n = a.size();
vector<array<ll, 3>> cand;
cand.reserve(n * 6);
for(ll i = 0; i < n; i++) {
for(ll d = 0; d < 1; d++) {
ll j = i + a[i];
if(j >= n) continue;
ll k = j + a[j];
if(k >= n) continue;
array<ll, 3> temp = {i, j, k};
if(i < j && j < k) cand.push_back(temp);
}
for(ll d = 0; d < 1; d++) {
ll j = i + a[i];
if(j >= n) continue;
ll k = i + a[j];
if(k >= n) continue;
array<ll, 3> temp = {i, j, k};
if(i < j && j < k) cand.push_back(temp);
}
for(ll d = 0; d < 1; d++) {
ll k = i + a[i];
if(k >= n) continue;
ll j = k - a[k];
if(j >= n || j <= i) continue;
array<ll, 3> temp = {i, j, k};
if(i < j && j < k) cand.push_back(temp);
}
}
for(ll j = 0; j < n; j++) {
for(ll d = 0; d < 1; d++) {
ll i = j - a[j];
if(i < 0) continue;
ll k = j + a[i];
if(k >= n) continue;
array<ll, 3> temp = {i, j, k};
if(i < j && j < k) cand.push_back(temp);
}
for(ll d = 0; d < 1; d++) {
ll k = j + a[j];
if(k >= n) continue;
ll i = j - a[k];
if(i < 0) continue;
array<ll, 3> temp = {i, j, k};
if(i < j && j < k) cand.push_back(temp);
}
}
for(ll k = 0; k < n; k++) {
ll j = k - a[k];
if(j < 0) continue;
ll i = k - a[j];
if(i < 0) continue;
array<ll, 3> temp = {i, j, k};
if(i < j && j < k) cand.push_back(temp);
}
sort(cand.begin(), cand.end());
cand.erase(unique(cand.begin(), cand.end()), cand.end());
ll ans = 0;
for(auto &[i, j, k] : cand) {
array<ll, 3> temp1 = {j - i, k - j, k - i};
array<ll, 3> temp2 = {a[i], a[j], a[k]};
sort(temp1.begin(), temp1.end());
sort(temp2.begin(), temp2.end());
if(temp1 == temp2) ans++;
}
return ans;
}
std::vector<int> construct_range(int M, int K) {
vector<int> res(M);
iota(res.begin(), res.end(), 0);
res[0] = 1;
return res;
}
