NTHUGE - Cái túi 3
Tác giả: hieult
Ngôn ngữ: C++
#include <set>
#include <map>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <cstdlib>
#include <cstring>
#include <sstream>
#include <iomanip>
#include <iostream>
#include <algorithm>
#include <ctime>
#include <deque>
#include <bitset>
#include <cctype>
#include <utility>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef unsigned int ui;
typedef unsigned long long ull;
#define Rep(i,n) for(int i = 0; i < (n); ++i)
#define Repd(i,n) for(int i = (n)-1; i >= 0; --i)
#define For(i,a,b) for(int i = (a); i <= (b); ++i)
#define Ford(i,a,b) for(int i = (a); i >= (b); --i)
#define Fit(i,v) for(__typeof((v).begin()) i = (v).begin(); i != (v).end(); ++i)
#define Fitd(i,v) for(__typeof((v).rbegin()) i = (v).rbegin(); i != (v).rend(); ++i)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define sz(a) ((int)(a).size())
#define all(a) (a).begin(), (a).end()
#define ms(a,x) memset(a, x, sizeof(a))
template<class F, class T> T convert(F a, int p = -1) {
stringstream ss;
if (p >= 0)
ss << fixed << setprecision(p);
ss << a;
T r;
ss >> r;
return r;
}
template<class T> T gcd(T a, T b) {
T r;
while (b != 0) {
r = a % b;
a = b;
b = r;
}
return a;
}
template<class T> T lcm(T a, T b) {
return a / gcd(a, b) * b;
}
template<class T> T sqr(T x) {
return x * x;
}
template<class T> T cube(T x) {
return x * x * x;
}
template<class T> int getbit(T s, int i) {
return (s >> i) & 1;
}
template<class T> T onbit(T s, int i) {
return s | (T(1) << i);
}
template<class T> T offbit(T s, int i) {
return s & (~(T(1) << i));
}
template<class T> int cntbit(T s) {
return s == 0 ? 0 : cntbit(s >> 1) + (s & 1);
}
const int bfsz = 1 << 16;
char bf[bfsz + 5];
int rsz = 0;
int ptr = 0;
char gc() {
if (rsz <= 0) {
ptr = 0;
rsz = (int) fread(bf, 1, bfsz, stdin);
if (rsz <= 0)
return EOF;
}
--rsz;
return bf[ptr++];
}
void ga(char &c) {
c = EOF;
while (!isalpha(c))
c = gc();
}
int gs(char s[]) {
int l = 0;
char c = gc();
while (isspace(c))
c = gc();
while (c != EOF && !isspace(c)) {
s[l++] = c;
c = gc();
}
s[l] = '\0';
return l;
}
template<class T> bool gi(T &v) {
v = 0;
char c = gc();
while (c != EOF && c != '-' && !isdigit(c))
c = gc();
if (c == EOF)
return false;
bool neg = c == '-';
if (neg)
c = gc();
while (isdigit(c)) {
v = v * 10 + c - '0';
c = gc();
}
if (neg)
v = -v;
return true;
}
typedef pair<int, int> II;
const ld PI = acos(-1.0);
const ld eps = 1e-12;
const int dr[] = { -1, 0, +1, 0};
const int dc[] = { 0, +1, 0, -1};
const int inf = (int) 1e9 + 5;
const ll linf = (ll) 1e18 + 5;
const int mod = (ll) (1e9 + eps);
using namespace std;
int n, m;
ll L, R;
ll w[35], c[35];
vector<pair<ll, ll> > V1, V2;
int main(){
// freopen("in.txt", "r", stdin);
cin >> n >> L >> R;
Rep(i, n) cin >> w[i] >> c[i];
m = n / 2;
n = n - n / 2;
Rep(mask, (1 << n)){
ll W = 0, C = 0;
Rep(i, n) if(getbit(mask, i)){
W += w[i];
C += c[i];
}
V1.pb(mp(W, C));
}
Rep(mask, (1 << m)){
ll W = 0, C = 0;
Rep(i, m) if(getbit(mask, i)){
W += w[i + n];
C += c[i + n];
}
V2.pb(mp(W, C));
}
V1.pb(mp(linf, 0)); V2.pb(mp(linf, 0)); V2.pb(mp(-1, 0));
sort(all(V1)); sort(all(V2));
multiset<ll> S;
multiset<ll>::iterator it;
// Rep(i, sz(V1)) cout << V1[i].fi << " "; puts("");
// Rep(i, sz(V2)) cout << V2[i].fi << " "; puts("");
int u = 0, v = 0;
while(u < sz(V2) - 1 && V2[u + 1].fi < L) u++;
while(v < sz(V2) - 1 && V2[v + 1].fi <= R) v++;
For(i, u + 1, v) S.insert(V2[i].se);
ll res = 0;
Rep(i, sz(V1)){
if(V1[i].fi > R) break;
while(u > 0 && V2[u].fi + V1[i].fi >= L) {
S.insert(V2[u].se);
u--;
}
while(v > 0 && V2[v].fi + V1[i].fi > R){
S.erase(S.find(V2[v].se));
v--;
}
if(!S.empty()){
it = S.end(); it--;
res = max(res, V1[i].se + (*it));
}
}
cout << res;
return 0;
}