Submission #1776764

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Source Code Expand

#include <bits/stdc++.h>
#define N 200010
#define int long long
using namespace std;
typedef long long ll;
inline int read()
{
	int x=0,f=1; char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')f=-1; ch=getchar();}
	while(ch>='0'&&ch<='9'){x=x*10+ch-'0'; ch=getchar();}
	return x*f;
}
int n,K,L[N],R[N],A[N],sl[N],cnt,Rt,B[N];
int tree[N*20],tot,ls[N*20],rs[N*20];
ll Ans,F[N]; //问题转化后,表示在第i转移之后站在第i个区间的最右端,还需走多少步能使选择合法
inline void deal(int &x,int y)
{
	if(!x) x=++tot; tree[x]=y;
}
inline void pushdown(int x)
{
	if(tree[x])
	{
		deal(ls[x],tree[x]);
		deal(rs[x],tree[x]);
		tree[x]=0;
	}
}
inline int query(int x,int l,int r,int &rt)
{
	if(!rt) rt=++tot;
	if(l==r||tree[rt]) return tree[rt];
	int mid=(l+r)>>1; pushdown(rt);
	if(x>mid) return query(x,mid+1,r,rs[rt]);
	else return query(x,l,mid,ls[rt]); 
}
inline void updata(int L,int R,int x,int l,int r,int &rt)
{
	if(L>R) return ;
	if(!rt) rt=++tot;
	if(L<=l&&r<=R)
	{
		deal(rt,x); return ;
	}
	int mid=(l+r)>>1; pushdown(rt);
	if(R>mid) updata(L,R,x,mid+1,r,rs[rt]);
	if(L<=mid) updata(L,R,x,l,mid,ls[rt]);
}
inline int calc(int l,int r,int x)
{
	if(l<=x&&x<=r) return 0;
	return (l-x+K)%K;
}
inline void solve(int l,int r,int rt)
{
	if(tree[rt])
	{
		Ans=min(Ans,F[tree[rt]]+(tree[rt]>cnt?0: calc(l,r,R[tree[rt]])));
		return ;
	}
	if(!rt||l==r) return ;
	int mid=(l+r)>>1; 
	solve(l,mid,ls[rt]); solve(mid+1,r,rs[rt]);
}
signed main()
{
	n=read(); K=read();
	ll all=0; Ans=1000000000000000000ll;
	for(int i=1;i<=n;i++)
	{
		int x=read(), y=read(); x<<=1;
		all+=x;
		if(y==1)
		{
			if(x>K) {puts("-1"); return 0;}
			++cnt; 
			L[cnt]=all%K; R[cnt]=((all-x)%K+K)%K;
			//cout << L[cnt] << " " << R[cnt] << endl; 
		}
	}
	deal(Rt,cnt+1);
	for(int i=cnt;i;i--)
	{
		int tx=query(R[i],0,K-1,Rt);
		F[i]=tx>cnt? 0: F[tx]+(R[i]-R[tx]+K)%K;
		if(L[i]<R[i])
		{
			if(L[i]) updata(0,L[i]-1,i,0,K-1,Rt);
			if(R[i]<K-1) updata(R[i]+1,K-1,i,0,K-1,Rt);
		}
		else updata(R[i]+1,L[i]-1,i,0,K-1,Rt);
	}
	solve(0,K-1,Rt);
	cout << Ans+all << endl;
	return 0;
}

Submission Info

Judge Result