Submission #209266

#	Time	Username	Problem	Language	Result	Execution time	Memory
209266		jzh	Foehn Phenomena (JOI17_foehn_phenomena)	C++14	10 / 100	165 ms	7416 KiB

foehn_phenomena

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
ll ft[2000005];
ll ls(ll x) { 
    return (x & (-x)); 
}
ll query(ll p) {
    ll sum = 0;
    for(; p; p -= ls(p)) sum += ft[p];
    return sum;
}

void update(ll x, ll y, ll v) {
	for(; x < 2000005; x += ls(x)) ft[x] += v;
    y++;
    for(; y < 2000005; y += ls(x)) ft[y] -= v;}
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    ll n,q,i,s,t,i1,x,y,w,sum=0,xi,yi;
    cin>>n>>q>>s>>t;
    ll arr[n+1];
    for (i=0;i<=n;i++){
        cin>>arr[i];
        if (i>0)update(i,i,arr[i]);
    }
    for (i=1;i<=n;i++){
        if (arr[i]>arr[i-1])sum-=s*(arr[i]-arr[i-1]);
        else sum+=t*(arr[i-1]-arr[i]);
    }
    //cout<<sum<<'\n';
    //cout<<query(0)<<'\n';
    while (q--){
        cin>>x>>y>>w;
        xi=query(x)-query(x-1);
        if (y!=n)yi=query(y+1)-query(y);
        else yi=0;
        if (xi>0)sum+=s*xi;
        else sum+=t*xi;
        if (yi>0)sum+=s*yi;
        else sum+=t*yi;
        update(x,y,w);
        xi=query(x)-query(x-1);
        if (y!=n)yi=query(y+1)-query(y);
        else yi=0;
        if (xi>0)sum-=s*xi;
        else sum-=t*xi;
        if (yi>0)sum-=s*yi;
        else sum-=t*yi;
        cout<<sum<<'\n';
    }

}

Compilation message (stderr)

foehn_phenomena.cpp: In function 'int main()':
foehn_phenomena.cpp:21:18: warning: unused variable 'i1' [-Wunused-variable]
     ll n,q,i,s,t,i1,x,y,w,sum=0,xi,yi;
                  ^~

• Subtask 1: 0 / 30
• Subtask 2: 10 / 10
• Subtask 3: 0 / 60