#include #include #define SELECTER(_1,_2,_3,SELECT,...) SELECT #define rep1(i,n) for(int i=0;i<(int)n;++i) #define rep2(i,a,n) for(int i=(int)a;i<(int)n;++i) #define rep(...) SELECTER(__VA_ARGS__,rep2,rep1)(__VA_ARGS__) #define RSELECTER(_1, _2, _3, RSELECT, ...) RSELECT #define rrep1(i,n) for(int i=(int)n-1;i>=0;--i) #define rrep2(i,a,n) for(int i=(int)n-1;i>=(int)a;--i) #define rrep(...) RSELECTER(__VA_ARGS__, rrep2, rrep1)(__VA_ARGS__) #define all(a) a.begin(),a.end() #define rall(a) a.rbegin(),a.rend() #define fi first #define se second #define PrintR LogOutput #ifdef _DEBUG #define Log(...) LogOutput(__VA_ARGS__) #else #define Log(...) #endif using namespace std; using namespace atcoder; using ll=long long; using pii=pair; using pll=pair; using pdd=pair; using veci=vector; using vecpii=vector>; using vecll=vector; using vecpll=vector>; using vecpdd=vector>; using vecs=vector; using vecb=vector; using vecd=vector; using tp=tuple; using tpll=tuple; using mint=modint998244353; using mint10=modint1000000007; template istream& operator>>(istream& in, pair& a){return in >> a.first >> a.second;} template ostream& operator<<(ostream& out, const pair& a){return out << a.first << ' ' << a.second;} ostream& operator<<(ostream& out, const mint& a){return out << a.val();} ostream& operator<<(ostream& out, const mint10& a){return out << a.val();} ostream& operator<<(ostream& out, const modint& a){return out << a.val();} template ostream& operator<<(ostream& out, const vector& d){for(int i = 0 ; i < d.size() ; ++i) out << d[i] << ' '; return out;} template pair operator+(const pair& a, const pair& b){return {a.fi + b.fi, a.se + b.se};} template pair operator-(const pair& a, const pair& b){return {a.fi - b.fi, a.se - b.se};} template inline bool chmax(T& a,T b){if(a inline bool chmin(T& a,T b){if(a>b) {a=b;return true;} return false;} constexpr ll INF=numeric_limits::max() / 4; constexpr ll MOD=998244353; template void LogOutput(Args&&... args){ stringstream ss; ((ss << args << ' '), ...); cout << ss.str().substr(0, ss.str().length() - 1) << endl; } template void LogOutput(vector>& data){for(auto d : data) LogOutput(d);} int main(){ ios::sync_with_stdio(false); std::cin.tie(nullptr); int n;cin>>n; veci a(n); rep(i, n) cin>>a[i]; ll ans = 0; rep(i, n){ vecpii cnt(2001, {0, 0}); rep(j, i + 1, n - 1){ cnt[a[j]].fi++; cnt[a[j]].se += cnt[a[i] + 10].fi; if(a[j + 1] >= a[i] + 12){ ans += ll(cnt[a[i] + 10].fi) * cnt[a[j + 1] - 1].fi - cnt[a[j + 1] - 1].se; } } } cout<