#include using namespace std; #define rep(i, n) for(long long i=0;i<(long long)(n);i++) #define REP(i,k,n) for(long long i=k;i<(long long)(n);i++) #define pb emplace_back typedef long long ll; typedef vector vi; typedef vector vvi; template bool chmin(T&a,T b){if(a>b){a=b;return true;}return false;} const ll inf=1001001001001001001; int main(){ ll n;cin>>n; vvi dp(n,vi(n,inf)),table(n,vi(n,-1)),cost(n,vi(n)); vi v(n);rep(i,n)cin>>v[i]; rep(i,n)v[i]--; rep(l,n){ vi cnt(n); rep(i,l)cnt[v[i]]++; for(int i=n-1;i;i--)cnt[i-1]+=cnt[i]; ll sum=0; REP(r,l,n){ sum+=cnt[v[r]]; cost[l][r]=sum; } } ll t; function sol=[&](ll l,ll r,ll a,ll b){ if(l>=r)return; ll md=(l+r)/2; table[t][md]=min(b,md); dp[t][md]=dp[t-1][min(b,md)-1]+cost[min(b,md)][md]; rep(i,min(b,md)-a)if(chmin(dp[t][md],dp[t-1][min(b,md)-2-i]+cost[min(b,md)-i-1][md]))table[t][md]=min(b,md)-i-1; sol(l,md,a,table[t][md]); sol(md+1,r,table[t][md],b); }; rep(i,n)dp[0][i]=cost[0][i]; for(t=1;t