#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> ii;
typedef vector <int> vi;
typedef vector <ll> vl;
typedef vector<string> vs;
typedef vector<bool> vb;
typedef vector <char> vc;
typedef vector<ii> vii;
typedef vector<vi> vvi;
typedef vector<vl> vvl;
typedef vector<vc> vvc;
typedef vector<vs> vvs;
typedef pair<ll,ll> pl;
typedef double dou;
typedef vector<pl> vpl;
typedef unsigned long long ull;
typedef uint64_t i64;
typedef vector <pair<int,ii>> graph;
typedef priority_queue<ii,vii,greater<ii>> priority_graph;
typedef vector<ull> vull;
#define f first
#define s second
#define pb push_back
#define sz(x) int((x).size())
#define all(x) begin(x), end(x)
#define ts to_string
#define lb lower_bound
#define ub upper_bound
#define yes cout<<'Y'<<'E'<<'S'<<endl
#define no cout<<'N'<<'O'<<endl
#define nd "\n"
void setIO(string name=""){ios_base::sync_with_stdio(0);cin.tie(0);if(sz(name)){freopen((name+".in").c_str(),"r",stdin);freopen((name+".out").c_str(),"w",stdout);}}
ll gcd(ll a, ll b) {return b == 0 ? a : gcd(b, a % b);}
ll mcm(ll a, ll b) {return (a * b) / gcd(a, b);}
bool prime(ll n) {for(int i=2; i<=sqrt(n); i++) if(n%i==0) return false; return true;}
struct compii{bool operator()(const ii &a, const ii &b){if(a.f==a.s)return a.s<b.s;return a.f>b.f;}};
bool comp(int a, int b) {return a>b;}
ll binpow(ll n, ll x){ll ans=1; while(x){if(x&1){ans*=n;}n*=n; x>>=1;} return ans;}
namespace operators {
template<typename T1, typename T2>istream& operator>>(istream& in, pair<T1, T2>& x){in >> x.first >> x.second;return in;}
template<typename T1, typename T2>ostream& operator<<(ostream& out, pair<T1, T2> x){out << x.first << " " << x.second;return out;}
template<typename T1>istream& operator>>(istream& in, vector<T1>& x) {for (auto& i : x) in >> i;return in;}
template<typename T1>ostream& operator<<(ostream& out, vector<T1>& x) {for (auto& i : x) out << i << " ";return out;}
template<typename T1, typename T2>ostream& operator<<(ostream& out, vector<pair <T1,T2>>& x) {for (auto& i : x) out << i.f << " "<<i.s;return out;}
template<typename T1, typename T2>istream& operator>>(istream& in, vector<pair <T1,T2>>& x) {for (auto& i : x) in >> i.f >>i.s;return in;}
}
using namespace operators;
int dx[]= {1,0,-1,0};
int dy[]= {0,1,0,-1};
const int mod=1e9+7;
const ll inf=1e18;
int n;
vl ft1,ft2;
int lsb(int x){
return x & (-x);
}
ll query(int ind, bool who){
ll res=0;
while(ind){
if(who) res+=ft1[ind];
else res+=ft2[ind];
ind-=lsb(ind);
}
return res;
}
void update(int ind, ll value, bool who){
while(ind<=n){
if(who) ft1[ind]+=value;
else ft2[ind]+=value;
ind+=lsb(value);
}
}
void solve()
{
cin>>n;
ft1.assign(n+1,0); ft2.assign(n+1,0);
ll a[n];
vpl aux(n);
for(int i=0; i<n; i++){
int x; cin>>x; aux[i]={x,i};
}
sort(all(aux)); a[aux[0].s]=1; int temp=1;
for(int i=1; i<n; i++){
if(aux[i].f==aux[i-1].f) a[aux[i].s]=temp;
else temp++, a[aux[i].s]=temp;
}
//for(auto &x: a) cout<<x<<" "; cout<<endl;
ll mx=0;
for(int i=n-1; i>=0; i--){
mx=max(mx,a[i]);
update(a[i],1,1);
}
//cout<<query(mx-1,1)<<endl;
//int top=n+99;
ll ans=0;
for(int i=0; i<n; i++){
update(a[i],-1,1);
//cout<<query(a[i]-1,0)<<" "<<query(a[i]-1,1)<<endl;
ans+=query(a[i]-1,0)*(query(a[i]-1,1));
update(a[i],1,0);
}
cout<<ans<<endl;
}
int main ()
{
setIO("");
int t=1;
//cin>>t;
while(t-->0) solve();
return 0;
}
Compilation message
Mountains.cpp: In function 'void setIO(std::string)':
Mountains.cpp:36:88: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
36 | void setIO(string name=""){ios_base::sync_with_stdio(0);cin.tie(0);if(sz(name)){freopen((name+".in").c_str(),"r",stdin);freopen((name+".out").c_str(),"w",stdout);}}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Mountains.cpp:36:128: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
36 | void setIO(string name=""){ios_base::sync_with_stdio(0);cin.tie(0);if(sz(name)){freopen((name+".in").c_str(),"r",stdin);freopen((name+".out").c_str(),"w",stdout);}}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
212 KB |
Output is correct |
| 2 |
Execution timed out |
2096 ms |
11988 KB |
Time limit exceeded |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
2091 ms |
11972 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
2091 ms |
11972 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
2091 ms |
11972 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
212 KB |
Output is correct |
| 2 |
Execution timed out |
2096 ms |
11988 KB |
Time limit exceeded |
| 3 |
Halted |
0 ms |
0 KB |
- |
