Submission #1085146

#	Time	Username	Problem	Language	Result	Execution time	Memory
1085146		vjudge1	Flooding Wall (BOI24_wall)	C++17	12 / 100	229 ms	33740 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define all(x) x.begin(),x.end()
#define pb push_back
#define for1(i,x,n) for(int i=x;i<=n;i++)
#define for2(i,x,n) for(int i=x;i>=n;i--)
#define int ll

typedef long long ll;
typedef pair<int,int> pii;

const ll maxn=5e5+69;
const ll mod=1e9+7;
const ll inf=1e18;
int n,a[maxn],b[maxn];
int mu2[maxn],chia2;

namespace subdevaicalon
{
    int m;
    vector<int> tmp;
    int aa[maxn],bb[maxn],res[maxn];
    struct segtree
    {
        int f[maxn*8],g[maxn*8],lazy[maxn*8];
        void push(int id)
        {
            int t=lazy[id];
            f[id*2]=(f[id*2]*t)%mod;
            f[id*2+1]=(f[id*2+1]*t)%mod;
            g[id*2]=(g[id*2]*t)%mod;
            g[id*2+1]=(g[id*2+1]*t)%mod;
            lazy[id*2]=lazy[id*2]*t%mod;
            lazy[id*2+1]=lazy[id*2+1]*t%mod;
            lazy[id]=-1;
        }
        void Add(int u,int val,int id=1,int l=0,int r=m)
        {
            if (l==r)
            {
                f[id]+=val;
                g[id]=f[id]*tmp[l];
                f[id]%=mod;
                g[id]%=mod;
                return;
            }
            if (lazy[id]!=-1) push(id);
            int mid=l+r>>1;
            if (u<=mid) Add(u,val,id*2,l,mid);
            else Add(u,val,id*2+1,mid+1,r);
            f[id]=(f[id*2]+f[id*2+1])%mod;
            g[id]=(g[id*2]+g[id*2+1])%mod;
        }
        void Mul(int u,int v,int val,int id=1,int l=0,int r=m)
        {
            if (u>r || v<l) return;
            if (u<=l&& r<=v)
            {
                f[id]=(f[id]*val)%mod;
                g[id]=(g[id]*val)%mod;
                lazy[id]=lazy[id]*val%mod;
//                if (u==0 && v==m) cerr<< id<<'\n';
                return;
            }
            int mid=l+r>>1;
            if (lazy[id]!=-1) push(id);
            Mul(u,v,val,id*2,l,mid);
            Mul(u,v,val,id*2+1,mid+1,r);
            f[id]=(f[id*2]+f[id*2+1])%mod;
            g[id]=(g[id*2]+g[id*2+1])%mod;
        }
        int Get_fsum(int u,int v,int id=1,int l=0,int r=m)
        {
            if (u>r || v<l) return 0;
            if (u<=l && r<=v) return f[id];
            int mid=l+r>>1;
            if (lazy[id]!=-1) push(id);
            return (Get_fsum(u,v,id*2,l,mid) + Get_fsum(u,v,id*2+1,mid+1,r))%mod;
        }
        int Get_gsum(int u,int v,int id=1,int l=0,int r=m)
        {
            if (u>r || v<l) return 0;
            if (u<=l && r<=v) return g[id];
            int mid=l+r>>1;
            if (lazy[id]!=-1) push(id);
            return (Get_gsum(u,v,id*2,l,mid) + Get_gsum(u,v,id*2+1,mid+1,r))%mod;
        }
    }tree;
    void Update(int i)
    {
        tree.Mul(bb[i]+1,m,2);
        tree.Add(bb[i],tree.Get_fsum(0,bb[i]));
        tree.Add(aa[i],tree.Get_fsum(0,aa[i]-1));
        tree.Mul(0,aa[i]-1,0);
    }
    int Get(int i)
    {
        int res=0;
        int r1=tree.Get_fsum(bb[i]+1,m), r2=tree.Get_gsum(bb[i]+1,m);
        r1=r1*chia2%mod;
        r2=r2*chia2%mod;
        res=r2+mod-(r1*b[i]%mod);
        res%=mod;
        int fb=tree.Get_fsum(bb[i],bb[i]);
        int xx=tree.Get_fsum(aa[i],bb[i]-1);
        fb-=xx;
        fb=fb*chia2%mod;
        r1+=xx+fb;
        r2+=tree.Get_gsum(aa[i],bb[i]-1);
        r2+=fb*b[i];
        r1%=mod;
        r2%=mod;
        res+=r2+mod-(r1*a[i]%mod);
        return res%mod;
    }
    void sol()
    {
        for1(i,1,n)
        {
            tmp.pb(a[i]);
            tmp.pb(b[i]);
        }
        tmp.pb(0);
        sort(all(tmp));
        tmp.resize(unique(all(tmp))-tmp.begin());
        m=tmp.size();
        for1(i,1,n)
        {
            aa[i]=lower_bound(all(tmp),a[i])-tmp.begin();//tmp[aa[i]]=a[i]
            bb[i]=lower_bound(all(tmp),b[i])-tmp.begin();
        }
        for1(i,0,m*4) tree.lazy[i]=-1;
        tree.Add(0,1);
        for1(i,1,n)
        {
            Update(i);
//            if (i==1)cerr << tree.Get_fsum(1,1)<<'\n';
            res[i]=Get(i)*mu2[n-i]%mod;
        }
        for1(i,0,m*4)
        {
            tree.lazy[i]=-1;
//            tree.f[i]=0;
//            tree.g[i]=0;
        }
        tree.Mul(0,m,0);
        tree.Add(0,1);
        for2(i,n,1)
        {
            Update(i);
//            cerr<< Get(i)<<'\n';
            res[i]=(res[i]+ (Get(i)*mu2[i-1]%mod))%mod;
        }
        int ans=0;
        for1(i,1,n)
        {
            ans=ans+res[i]+mod-Get(i);
            ans%=mod;
        }
        cout << ans;
    }
}
void sol()
{
//    cerr<< pw(2,mod-2);
    chia2=500000004;
    cin >> n;
    for1(i,1,n)
    {
        cin >> a[i];
//        cerr<< "aaa\n";
    }
    bool is_sub2=1;
    mu2[0]=1;
    for1(i,1,n) mu2[i]=mu2[i-1]*2%mod;
    for1(i,1,n)
    {
        cin >> b[i];
        if (b[i]<a[i]) swap(a[i],b[i]);
        if (a[i]!=1 || b[i]!=2) is_sub2=0;
    }

    subdevaicalon::sol();

}

int32_t main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
//    freopen("wall.inp","r",stdin);
//    freopen("wall.out","w",stdout);
    int t=1;//cin >> t;
    while (t--)
    {
        sol();
    }
}
/*

10
1 2 3 4 5 6 7 8 9 10
10 9 8 7 6 5 4 3 2 1
*/

Compilation message (stderr)

Main.cpp: In member function 'void subdevaicalon::segtree::Add(ll, ll, ll, ll, ll)':
Main.cpp:51:22: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   51 |             int mid=l+r>>1;
      |                     ~^~
Main.cpp: In member function 'void subdevaicalon::segtree::Mul(ll, ll, ll, ll, ll, ll)':
Main.cpp:68:22: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   68 |             int mid=l+r>>1;
      |                     ~^~
Main.cpp: In member function 'll subdevaicalon::segtree::Get_fsum(ll, ll, ll, ll, ll)':
Main.cpp:79:22: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   79 |             int mid=l+r>>1;
      |                     ~^~
Main.cpp: In member function 'll subdevaicalon::segtree::Get_gsum(ll, ll, ll, ll, ll)':
Main.cpp:87:22: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   87 |             int mid=l+r>>1;
      |                     ~^~
Main.cpp: In function 'void sol()':
Main.cpp:176:10: warning: variable 'is_sub2' set but not used [-Wunused-but-set-variable]
  176 |     bool is_sub2=1;
      |          ^~~~~~~

• Subtask 1: 0 / 8
• Subtask 2: 0 / 17
• Subtask 3: 0 / 19
• Subtask 4: 0 / 14
• Subtask 5: 12 / 12
• Subtask 6: 0 / 30