Submission #1104053

#	Time	Username	Problem	Language	Result	Execution time	Memory
1104053		modwwe	Heavy Light Decomposition (CCO24_day2problem2)	C++17	25 / 25	860 ms	51460 KiB

Main

#pragma GCC optimize("Ofast,unroll-loops")
//#pragma GCC optimize("conserve-stack")
#include<bits/stdc++.h>
//#define int long long
#define ll long long
#define down cout<<'\n';
#define debug cout<<" cucuucucuuu",down
#define NHP     ios_base::sync_with_stdio(0);cout.tie(0);cin.tie(0);
#define modwwe  int t;cin>>t; while(t--)
#define bit(i,j) (i>>j&1)
#define sobit(a) __builtin_popcountll(a)
#define task "test"
#define fin(x) freopen(x".inp","r",stdin)
#define fou(x) freopen(x".out","w",stdout)
#define pb push_back
#define mask(i) (1<<i)
#define checktime   cerr << (double)clock() / CLOCKS_PER_SEC * 1000  << " ms";
using namespace std;
#define getchar_unlocked getchar

inline int scan()
{
    char c = getchar_unlocked();
    int x = 0;
    while (c < '0' || c > '9')
    {
        c = getchar_unlocked();
    }
    while (c >= '0' && c <= '9')
    {
        x = (x << 1) + (x << 3) + c - '0';
        c = getchar_unlocked();
    }
    return x;
};
void phongbeo();
const int inf = 1e9;
const int mod2 = 1000003;
const int  mod1 = 998244353;
int add(int x,int y)
{
    if(x+y>=mod2) x-=mod2;
    if(x+y<0) x+=mod2;
    return x+y;
}
struct icd
{
    long double a;
    int b;
};
struct ib
{
    int a;
    int b;
};
struct ic
{
    int a, b, c, d;
};
struct ie
{
    int a, b, c, d, e;

};

ll n, m, s1, s2, s4, s3, sf, k, s5, s6, mx, s7, s8, s9, mx2, res, dem2 = 0, dem = 0, s33, dem3, dem4, mid, l2, r2, center;
int  i, s10, s12,k1,k2,k3,s11,limit,w,l,r,last,root;
int kk;
int el = 19;

main()
{
    if(fopen(task".inp","r"))
    {
        fin(task);
        fou(task);
    }
    NHP
    /// cin>>s1;
///modwwe
    phongbeo();
    // checktime
}
int c[500001];
int pre[500001];
int nxt[500001];
int a[500001];
int dp[500001];
vector<int> v2[500002];
int f[500002];
ib mer(ib a,ib b)
{
    if(a.b<b.b) return a;
    if(b.b<a.b) return b;
    return {add(a.a,b.a),a.b};
}
struct IT
{
    ib t[2000009];
    int t2[2000009];
    void ff(int x)
    {
        for(int i=x*2; i<=x*2+1; i++)
        {
            t[i].b=add(t[i].b,t2[x]);
            t2[i]=add(t2[i],t2[x]);
        }
        t2[x]=0;
    }
    void upd(int node,int l,int r,int l1,int r1,bool f,int x)
    {
        if(l>r1||r<l1) return;
        if(l>=l1&&r<=r1)
        {
            if(!f)t[node].b=add(t[node].b,x),t2[node]=add(t2[node],x);
            else t[node].a=add(t[node].a,x);
            return;
        }
        int mid=l+r>>1;
        if(t2[node]!=0)
            ff(node);
        upd(node<<1,l,mid,l1,r1,f,x);
        upd(node<<1|1,mid+1,r,l1,r1,f,x);
        t[node]=mer(t[node<<1],t[node<<1|1]);
    }
} st[2];
void upd(int x)
{
    if(pre[x]!=0)
    {
        st[1-pre[x]%2].upd(1,0,n,pre[pre[x]],pre[x]-1,0,-1);
        if(a[pre[x]]!=a[pre[x]+1])
        {
            st[pre[x]%2].upd(1,0,n,pre[x],pre[x],1,-dp[pre[x]-1]);
        }
                st[x%2].upd(1,0,n,0,pre[x]-1,0,1);
    }
    st[1-x%2].upd(1,0,n,pre[x],x-1,0,1);
    if(pre[x]!=0&&x%2!=pre[x]%2)
    {
        st[1].upd(1,0,n,0,pre[x]-1,0,1);
        st[0].upd(1,0,n,0,pre[x]-1,0,1);
    }
}
void phongbeo()
{
    cin>>n;
    for(int i=1; i<=n; i++)
        cin>>a[i];
    for(int i=1; i<=n; i++)
    {
        pre[i]=c[a[i]];
        c[a[i]]=i;
    }
    for(int i=1; i<=n; i++)
        c[i]=n+1;
    for(int i=n; i>=1; --i)
    {
        nxt[i]=c[a[i]];
        c[a[i]]=i;
    }
    st[0].upd(1,0,n,0,0,1,1);
    dp[0]=1;
    for(int i=1; i<=n; i++)
    {
        upd(i);
        ib x=mer(st[0].t[1],st[1].t[1]);
            dp[i]=add(x.a,dp[i-1]);
        st[i%2].upd(1,0,n,i,i,1,dp[i]);
        if(a[i]!=a[i-1]&&i>=2)
            st[1-i%2].upd(1,0,n,i-1,i-1,1,dp[i-2]);
    }
    cout<<dp[n];
}

Compilation message (stderr)

Main.cpp:71:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   71 | main()
      | ^~~~
Main.cpp: In member function 'void IT::upd(int, int, int, int, int, bool, int)':
Main.cpp:119:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  119 |         int mid=l+r>>1;
      |                 ~^~
Main.cpp: In function 'int main()':
Main.cpp:13:23: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 | #define fin(x) freopen(x".inp","r",stdin)
      |                ~~~~~~~^~~~~~~~~~~~~~~~~~~
Main.cpp:75:9: note: in expansion of macro 'fin'
   75 |         fin(task);
      |         ^~~
Main.cpp:14:23: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 | #define fou(x) freopen(x".out","w",stdout)
      |                ~~~~~~~^~~~~~~~~~~~~~~~~~~~
Main.cpp:76:9: note: in expansion of macro 'fou'
   76 |         fou(task);
      |         ^~~

• Subtask 1: 3 / 3
• Subtask 2: 4 / 4
• Subtask 3: 5 / 5
• Subtask 4: 6 / 6
• Subtask 5: 7 / 7