Submission #510113

#	Time	Username	Problem	Language	Result	Execution time	Memory
510113		ETK	Swap Swap Sort (CCO21_day1problem1)	C++14	25 / 25	3249 ms	88188 KiB

Main

#include <bits/stdc++.h>
#define rep(i,a,b) for(int i=(a);i<=(b);++i)
#define per(i,a,b) for(int i=(a);i>=(b);--i)
#define pii pair<int,int>
#define vi vector<int>
#define mp make_pair
#define fi first
#define se second
#define pb push_back
#define debug(...) fprintf(stderr, __VA_ARGS__)
#define ALL(x) x.begin(),x.end()
#define sz(x) int(x.size())
#define ll long long
using namespace std;
inline ll read(){
    ll x=0,f=1;char ch=getchar();
    while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}
    while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
    return x*f;
}
const int N=2e5+5;
int n,k,q,id[N],a[N];
int t[N];
void add(int x,int v){for(;x <= n;x += x & -x)t[x] += v;}
ll Q(int x){
    ll res = 0;
    for(;x;x -= x & -x)res += t[x];
    return res;
}
vector <int> pos[N];
map <pii,ll> S;
ll work(int a,int b){
    ll tot = (ll)sz(pos[a]) * sz(pos[b]);
    if(S.count(mp(a,b)))return S[mp(a,b)];
    if(S.count(mp(b,a)))return tot - S[mp(b,a)];
    ll res = 0;
    if(sz(pos[a]) < sz(pos[b])){
        for(auto x : pos[a])
            res += lower_bound(ALL(pos[b]),x) - pos[b].begin();
    }else{
        for(auto x : pos[b])
            res += pos[a].end() - upper_bound(ALL(pos[a]),x);
    }
    return S[mp(a,b)] = res;
}
int main(){
    n = read(),k = read(),q = read();
    rep(i,1,n){
        a[i] = read();
        pos[a[i]].pb(i);
    }
    rep(i,1,n)id[i] = i;
    ll ans = 0;
    rep(i,1,n){
        ans += Q(k) - Q(a[i]);
        add(a[i],1);
    }
    while(q--){
        int x = read();
        ans += (ll)sz(pos[id[x]]) * sz(pos[id[x+1]]) - 2 * work(id[x],id[x+1]);
        printf("%lld\n",ans);
        swap(id[x],id[x+1]);
    }
    return 0;
}

• Subtask 1: 3 / 3
• Subtask 2: 3 / 3
• Subtask 3: 5 / 5
• Subtask 4: 14 / 14