Submission #317262

#	Time	Username	Problem	Language	Result	Execution time	Memory
317262		nandonathaniel	Foehn Phenomena (JOI17_foehn_phenomena)	C++14	100 / 100	652 ms	19832 KiB

foehn_phenomena

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const LL MAXN=200005;

LL tree[4*MAXN],lazy[4*MAXN];
LL A[MAXN];

void updatenode(LL now,LL L,LL R,LL val){
	tree[now]+=((R-L+1)*val);
	lazy[now]+=val;
}


void pushdown(LL now,LL L,LL R){
	LL mid=(L+R)/2;
	updatenode(2*now,L,mid,lazy[now]);
	updatenode(2*now+1,mid+1,R,lazy[now]);
	lazy[now]=0;
}

void build(LL now,LL L,LL R){
	if(L==R){
		tree[now]=A[L];
		return;
	}
	LL mid=(L+R)/2;
	build(2*now,L,mid);
	build(2*now+1,mid+1,R);
	tree[now]=tree[2*now]+tree[2*now+1];
}

LL query(LL now,LL L,LL R,LL x,LL y){
	if(L>=x && R<=y)return tree[now];
	if(L>y || R<x)return 0;
	pushdown(now,L,R);
	LL mid=(L+R)/2;
	return query(2*now,L,mid,x,y)+query(2*now+1,mid+1,R,x,y);
}

void update(LL now,LL L,LL R,LL x,LL y,LL val){
	if(L>=x && R<=y){
		updatenode(now,L,R,val);
		return;
	}
	if(L>y || R<x)return;
	LL mid=(L+R)/2;
	pushdown(now,L,R);
	update(2*now,L,mid,x,y,val);
	update(2*now+1,mid+1,R,x,y,val);
	tree[now]=tree[2*now]+tree[2*now+1];
}

int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	LL N,Q,S,T,L,R,P,U,V,W,X;
	cin >> N >> Q >> S >> T;
	for(LL i=0;i<=N;i++)cin >> A[i];
	build(1,1,N);
	LL ans=0;
	for(LL i=1;i<=N;i++){
		if(A[i-1]<=A[i])ans-=(S*(A[i]-A[i-1]));
		else ans+=(T*(A[i-1]-A[i]));
	}
	while(Q--){
		cin >> L >> R >> P;
		LL U=0,V=query(1,1,N,L,L);
		if(L>=2)U=query(1,1,N,L-1,L-1);
		if(U<=V)ans+=(S*(V-U));
		else ans-=(T*(U-V));
		LL W=query(1,1,N,R,R),X;
		if(R+1<=N){
			X=query(1,1,N,R+1,R+1);
			if(W<=X)ans+=(S*(X-W));
			else ans-=(T*(W-X));
		}
		update(1,1,N,L,R,P);
		V=query(1,1,N,L,L);
		W=query(1,1,N,R,R);
		if(U<=V)ans-=(S*(V-U));
		else ans+=(T*(U-V));
		if(R+1<=N){
			if(W<=X)ans-=(S*(X-W));
			else ans+=(T*(W-X));
		}
		cout << ans << '\n';
	}
	return 0;
}

Compilation message (stderr)

foehn_phenomena.cpp: In function 'int main()':
foehn_phenomena.cpp:56:19: warning: unused variable 'U' [-Wunused-variable]
   56 |  LL N,Q,S,T,L,R,P,U,V,W,X;
      |                   ^
foehn_phenomena.cpp:56:21: warning: unused variable 'V' [-Wunused-variable]
   56 |  LL N,Q,S,T,L,R,P,U,V,W,X;
      |                     ^
foehn_phenomena.cpp:56:23: warning: unused variable 'W' [-Wunused-variable]
   56 |  LL N,Q,S,T,L,R,P,U,V,W,X;
      |                       ^
foehn_phenomena.cpp:56:25: warning: unused variable 'X' [-Wunused-variable]
   56 |  LL N,Q,S,T,L,R,P,U,V,W,X;
      |                         ^
foehn_phenomena.cpp:84:19: warning: 'X' may be used uninitialized in this function [-Wmaybe-uninitialized]
   84 |    else ans+=(T*(W-X));
      |                 ~~^~~

• Subtask 1: 30 / 30
• Subtask 2: 10 / 10
• Subtask 3: 60 / 60