#include <bits/stdc++.h>
#define fr(i, n, m) for(int i = (n); i < (m); i ++)
#define pb push_back
#define st first
#define nd second
#define pq priority_queue
#define all(x) begin(x), end(x)
#include <time.h>
#include <cmath>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
const int i_inf = 1e9;
const ll inf = 1e18;
const ll mod = 1000000007;
const ld eps = 1e-13;
const ld pi = 3.14159265359;
mt19937 _rand(time(NULL));
clock_t timer = clock();
const int mxn = 5e5;
const ll A = 911382323;
const ll B = 972663749;
ll modpow(ll x, ll n){
if(n == 0) return 1%mod;
ll u = modpow(x, n/2);
u = (u * u) % mod;
if(n % 2) u = (u * x) % mod;
return u;
}
ll inverse(ll x){
return modpow(x, mod-2);
}
ll add(ll ans, ll val){
ans = (ans + val) % mod;
return ans;
}
ll mul(ll ans, ll val){
ans = (ans * val) % mod;
return ans;
}
ll sub(ll ans, ll val){
ans = (ans - val) % mod;
if(ans < 0) ans += mod;
return ans;
}
ll _div(ll ans, ll val){
ans = (ans * inverse(val)) % mod;
return ans;
}
ll fakt[mxn];
ll bc(ll n, ll k){
return (fakt[n]*inverse((fakt[k]*fakt[n-k])%mod))%mod;
}
ll sq(ll x){
return x*x;
}
ll rsum(ll a, ll b){
return (b-a+1)*(a+b)/2;
}
void prec(){
fakt[0] = 1;
fr(i, 1, mxn){
fakt[i] = mul(fakt[i-1], i);
}
}
int bit[mxn];
void update(int k, int val){
while(k < mxn){
bit[k] += val;
k += k&-k;
}
}
int sum(int k){
int s = 0;
while(k > 0){
s += bit[k];
k -= k&-k;
}
return s;
}
void solve(){
int n;
cin >> n;
int a[n];
vector<pii> v;
fr(i, 0, n){
cin >> a[i];
v.pb({a[i], i});
}
cout<<0<<endl;
return;
sort(all(v));
int val = 0;
int pr = -1;
for(auto u : v){
if(u.st != pr) pr = u.st, ++val;
a[u.nd] = val;
}
ll le[n];
ll ri[n];
fr(i, 0, n){
le[i] = sum(a[i]-1);
update(a[i], +1);
}
fr(i, 0, n) update(a[i],-1);
for(int i = n-1; i >= 0; i --){
ri[i] = sum(a[i]-1);
update(a[i], +1);
}
ll ans = 0;
fr(i, 0, n){
ans += le[i]*ri[i];
}
cout<<ans<<endl;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
solve();
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
384 KB |
Output is correct |
2 |
Correct |
8 ms |
4596 KB |
Output is correct |
3 |
Correct |
7 ms |
4596 KB |
Output is correct |
4 |
Correct |
10 ms |
4596 KB |
Output is correct |
5 |
Correct |
9 ms |
4596 KB |
Output is correct |
6 |
Correct |
10 ms |
4596 KB |
Output is correct |
7 |
Correct |
7 ms |
4596 KB |
Output is correct |
8 |
Correct |
8 ms |
4596 KB |
Output is correct |
9 |
Correct |
7 ms |
4596 KB |
Output is correct |
10 |
Correct |
8 ms |
4596 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
23 ms |
5612 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
23 ms |
5612 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
0 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
0 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
23 ms |
5612 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
384 KB |
Output is correct |
2 |
Correct |
8 ms |
4596 KB |
Output is correct |
3 |
Correct |
7 ms |
4596 KB |
Output is correct |
4 |
Correct |
10 ms |
4596 KB |
Output is correct |
5 |
Correct |
9 ms |
4596 KB |
Output is correct |
6 |
Correct |
10 ms |
4596 KB |
Output is correct |
7 |
Correct |
7 ms |
4596 KB |
Output is correct |
8 |
Correct |
8 ms |
4596 KB |
Output is correct |
9 |
Correct |
7 ms |
4596 KB |
Output is correct |
10 |
Correct |
8 ms |
4596 KB |
Output is correct |
11 |
Incorrect |
23 ms |
5612 KB |
Output isn't correct |
12 |
Halted |
0 ms |
0 KB |
- |