oj.uz

Submission #392860

# Submission time Handle Problem Language Result Execution time Memory
392860 2021-04-22T02:59:34 Z ignaciocanta Knapsack (NOI18_knapsack) C++14
100 / 100
 95 ms 4116 KB 
#include <bits/stdc++.h>
 
using namespace std;
 
using tint = long long;
using ld = long double;
 
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)
 
using pi = pair<int,int>;
using pl = pair<tint,tint>;
using vi = vector<int>;
using vpi = vector<pi>;
using vpl = vector<pl>;
using vvi = vector<vi>;
using vl = vector<tint>;
using vb = vector<bool>;
 
#define pb push_back
#define pf push_front
#define rsz resize
#define all(x) begin(x), end(x)
#define rall(x) x.rbegin(), x.rend() 
#define sz(x) (int)(x).size()
#define ins insert
 
#define f first
#define s second
#define mp make_pair
 
#define DBG(x) cerr << #x << " = " << x << endl;
 
const int MOD = 1e9+7; 
const tint mod = 998244353;
const int MX = 20000005;
const tint INF = 1e18; 
const int inf = 2e9;
const ld PI = acos(ld(-1)); 
const ld eps = 1e-5;
 
const int dx[4] = {1, -1, 0, 0};
const int dy[4] = {0, 0, 1, -1};
 
template<class T> void remDup(vector<T> &v){ 
	sort(all(v)); v.erase(unique(all(v)),end(v));
}
 
template<class T> bool ckmin(T& a, const T& b) {
	return b < a ? a = b, 1 : 0; 
} 
template<class T> bool ckmax(T& a, const T& b) {
	return a < b ? a = b, 1 : 0; 
}
 
bool valid(int x, int y, int n, int m){
	return (0<=x && x<n && 0<=y && y<m);
}
 
int cdiv(int a, int b) { return a/b+((a^b)>0&&a%b); } //redondea p arriba
int fdiv(int a, int b) { return a/b-((a^b)<0&&a%b); } //redondea p abajo
 
void NACHO(string name = ""){
	ios_base::sync_with_stdio(0); cin.tie(0);
	if(sz(name)){
		freopen((name+".in").c_str(), "r", stdin);
		freopen((name+".out").c_str(), "w", stdout);
	}
}
 
// la solucion trivial es para cada objeto meter k individuales, y 
// luego correr knpascak normal. Sin embargo, hay 10^5 objetos y j <= 10^9.
// esto no es feasible.
// lo que queremos es basicamente descomponer el k en grupos de ese mismo
// objeto tal que con estos grupos puedo formar todas las sumas
// entre 1 y k y tal que la cantidad de grupos es chica.
// hacemos lo siguiente: vamos haciendo grupos de tamaño 2^0, 2^1, 2^2, hasta que
// no podamos seguir restando. A lo último metemos en un grupo lo que sobro.
// es obvio que podemos crear todas las sumas entre 1 y k con esto, y a su vez,
// hay logk grupos por cada objeto.
// sin embargo, esto no alcanza para llegar a 100.
// lo que tenemos que hacer es ver que para cada peso x,
// solo nos interesa ver los W/x items con mayor valor (ya que no puedo meter mas de W/x en la bolsa de capacidad W).
// Como los pesos van hasta 2000, la cantidad de items es a lo sumo 2000/1+2000/2+2000/3+2000/4...=17000 aprox.
// Esto ya da 100.
 
struct Item{
	tint v, w, k;
};
 
tint dp[2005];
vector<Item> items;
vpi ge[2005];
 
int main(){
	NACHO();
	tint n, w; cin >> w >> n;
	F0R(i, n){
		tint v, w, k; cin >> v >> w >> k;
		ge[w].pb(mp(v, k));
	}
	FOR(i, 1, 2005){
		sort(rall(ge[i]));
		int quan = w/i;
		F0R(j, sz(ge[i])){
			while(ge[i][j].s > 0 && quan > 0){
				--ge[i][j].s;
				--quan;
				items.pb({ge[i][j].f, i, 1});
			}
		}
	}
	F0R(i, sz(items)){
		R0F(j, w){
			if(j+items[i].k*items[i].w <= w) ckmax(dp[j+items[i].k*items[i].w], dp[j]+items[i].k*items[i].v);
		}
	}
	cout << dp[w] << "\n";
}

Compilation message

knapsack.cpp: In function 'void NACHO(std::string)':
knapsack.cpp:69:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   69 |   freopen((name+".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:70:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   70 |   freopen((name+".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 2 ms 332 KB Output is correct
3 Correct 2 ms 364 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 336 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 332 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 2 ms 332 KB Output is correct
3 Correct 2 ms 364 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 336 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 8 ms 332 KB Output is correct
13 Correct 2 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 332 KB Output is correct
17 Correct 1 ms 332 KB Output is correct
18 Correct 1 ms 332 KB Output is correct
19 Correct 2 ms 332 KB Output is correct
20 Correct 1 ms 332 KB Output is correct

Subtask #4
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 2 ms 332 KB Output is correct
7 Correct 2 ms 364 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 336 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 8 ms 332 KB Output is correct
17 Correct 2 ms 332 KB Output is correct
18 Correct 1 ms 332 KB Output is correct
19 Correct 1 ms 332 KB Output is correct
20 Correct 1 ms 332 KB Output is correct
21 Correct 1 ms 332 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 2 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 13 ms 472 KB Output is correct
27 Correct 1 ms 332 KB Output is correct
28 Correct 1 ms 332 KB Output is correct
29 Correct 1 ms 332 KB Output is correct
30 Correct 3 ms 332 KB Output is correct
31 Correct 1 ms 332 KB Output is correct
32 Correct 1 ms 332 KB Output is correct
33 Correct 1 ms 332 KB Output is correct
34 Correct 2 ms 332 KB Output is correct

Subtask #5
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 2 ms 332 KB Output is correct
7 Correct 2 ms 364 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 336 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 8 ms 332 KB Output is correct
17 Correct 2 ms 332 KB Output is correct
18 Correct 1 ms 332 KB Output is correct
19 Correct 1 ms 332 KB Output is correct
20 Correct 1 ms 332 KB Output is correct
21 Correct 1 ms 332 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 2 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 13 ms 472 KB Output is correct
27 Correct 1 ms 332 KB Output is correct
28 Correct 1 ms 332 KB Output is correct
29 Correct 1 ms 332 KB Output is correct
30 Correct 3 ms 332 KB Output is correct
31 Correct 1 ms 332 KB Output is correct
32 Correct 1 ms 332 KB Output is correct
33 Correct 1 ms 332 KB Output is correct
34 Correct 2 ms 332 KB Output is correct
35 Correct 33 ms 1456 KB Output is correct
36 Correct 51 ms 1508 KB Output is correct
37 Correct 46 ms 2380 KB Output is correct
38 Correct 36 ms 2632 KB Output is correct
39 Correct 43 ms 3400 KB Output is correct
40 Correct 95 ms 4116 KB Output is correct
41 Correct 63 ms 3312 KB Output is correct
42 Correct 67 ms 3332 KB Output is correct
43 Correct 93 ms 3364 KB Output is correct
44 Correct 87 ms 3332 KB Output is correct
45 Correct 45 ms 3652 KB Output is correct
46 Correct 40 ms 3136 KB Output is correct
47 Correct 50 ms 3828 KB Output is correct
48 Correct 66 ms 3880 KB Output is correct
49 Correct 37 ms 3416 KB Output is correct
50 Correct 71 ms 3860 KB Output is correct