Submission #112306

#	Time	Username	Problem	Language	Result	Execution time	Memory
112306		Mercenary	Foehn Phenomena (JOI17_foehn_phenomena)	C++14	100 / 100	163 ms	13176 KiB

foehn_phenomena

#include<bits/stdc++.h>

using namespace std;
#define taskname "A"
#define pb	push_back
#define mp 	make_pair
#ifndef LOCAL
#define cerr if(0)cout
#endif

typedef long double ld;
typedef long long ll;
typedef pair<int,int> ii;
const int maxn = 2e5 + 5;

int s , t , n  , q;

ll a[maxn] , b[maxn];

void update(int x , int delta){
    for( ; x <= n ; x += x & -x)
        a[x] += delta;
}

ll query(int x){
    ll res = 0;
    for( ; x > 0 ; x &= x - 1)
        res += a[x];
    return res;
}

ll get(ll pre , ll now , ll add){
    ll res = 0;
    if(pre <= now){
        res += (ll)s * (now - pre);
    }else res -= (ll)t * (pre - now);
    now += add;
    if(pre <= now){
        res -= (ll)s * (now - pre);
    }else res += (ll)t * (pre - now);
    return res;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen(taskname".INP","r")){
		freopen(taskname".INP", "r",stdin);
		freopen(taskname".OUT", "w",stdout);
    }
    cin >> n >> q >> s >> t;
    ll res = 0;
    for(int i = 0 ; i <= n ; ++i){
        cin >> b[i];
        if(i > 0){
            update(i,b[i]-b[i - 1]);
            if(b[i] >= b[i - 1]){
                res -= s * (ll)(b[i] - b[i - 1]);
//                cout << i << " ";
            }else{
                res += t * (ll)(b[i - 1] - b[i]);
            }
        }
//        cout << res << endl;
    }
    for(int i = 1 ; i <= q ; ++i){
        int x , y , val;cin >> x >> y >> val;
        res += get(query(x - 1) , query(x) , val);
        if(y != n)res += get(query(y) , query(y + 1) , -val);
        update(x,val);
        update(y + 1 , -val);
        cout << res << '\n';
    }
}

Compilation message (stderr)

foehn_phenomena.cpp: In function 'int main()':
foehn_phenomena.cpp:49:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".INP", "r",stdin);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
foehn_phenomena.cpp:50:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".OUT", "w",stdout);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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