Submission #313045

# Submission time Handle Problem Language Result Execution time Memory
313045 2020-10-15T06:02:43 Z vivaan_gupta Schools (IZhO13_school) C++14
100 / 100
130 ms 10736 KB
#include <bits/stdc++.h>
using namespace std;
 
using ll = long long;
using ld = long double;
using db = double; 
using str = string; // yay python!

using pi = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;

using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<db>; 
using vs = vector<str>;
using vpi = vector<pi>;
using vpl = vector<pl>; 
using vpd = vector<pd>;

#define tcT template<class T
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>; 
tcT, size_t SZ> using AR = array<T,SZ>; 

// pairs
#define mp make_pair
#define f first
#define s second
#define int long long
// vectors
#define sz(x) (int)(x).size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend() 
#define sor(x) sort(all(x)) 
#define rsz resize
#define ins insert 
#define ft front() 
#define bk back()
#define pf push_front 
#define pb push_back
#define eb emplace_back 
#define lb lower_bound 
#define ub upper_bound 

// loops
#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)

const int MOD = 1e9+7; // 998244353;
const int MX = 2e5+5;
const ll INF = 1e18; // not too close to LLONG_MAX
const ld PI = acos((ld)-1);
const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1}; // for every grid problem!!
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 

// helper funcs
constexpr int pct(int x) { return __builtin_popcount(x); } // # of bits set
constexpr int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x)) 
ll cdiv(ll a, ll b) { return a/b+((a^b)>0&&a%b); } // divide a by b rounded up
ll fdiv(ll a, ll b) { return a/b-((a^b)<0&&a%b); } // divide a by b rounded down

tcT> bool ckmin(T& a, const T& b) {
	return b < a ? a = b, 1 : 0; } // set a = min(a,b)
tcT> bool ckmax(T& a, const T& b) {
	return a < b ? a = b, 1 : 0; }

#define tcTU tcT, class U
tcTU> T fstTrue(T lo, T hi, U f) {
	hi ++; assert(lo <= hi); // assuming f is increasing
	while (lo < hi) { // find first index such that f is true 
		T mid = lo+(hi-lo)/2;
		f(mid) ? hi = mid : lo = mid+1; 
	} 
	return lo;
}
tcTU> T lstTrue(T lo, T hi, U f) {
	lo --; assert(lo <= hi); // assuming f is decreasing
	while (lo < hi) { // find first index such that f is true 
		T mid = lo+(hi-lo+1)/2;
		f(mid) ? lo = mid : hi = mid-1;
	} 
	return lo;
}
tcT> void remDup(vector<T>& v) { // sort and remove duplicates
	sort(all(v)); v.erase(unique(all(v)),end(v)); }
tcTU> void erase(T& t, const U& u) { // don't erase
	auto it = t.find(u); assert(it != end(t));
	t.erase(u); } // element that doesn't exist from (multi)set

// INPUT
#define tcTUU tcT, class ...U
tcT> void re(complex<T>& c);
tcTU> void re(pair<T,U>& p);
tcT> void re(vector<T>& v);
tcT, size_t SZ> void re(AR<T,SZ>& a);

tcT> void re(T& x) { cin >> x; }
void re(db& d) { str t; re(t); d = stod(t); }
void re(ld& d) { str t; re(t); d = stold(t); }
tcTUU> void re(T& t, U&... u) { re(t); re(u...); }

tcT> void re(complex<T>& c) { T a,b; re(a,b); c = {a,b}; }
tcTU> void re(pair<T,U>& p) { re(p.f,p.s); }
tcT> void re(vector<T>& x) { trav(a,x) re(a); }
tcT, size_t SZ> void re(AR<T,SZ>& x) { trav(a,x) re(a); }

// TO_STRING
#define ts to_string
str ts(char c) { return str(1,c); }
str ts(const char* s) { return (str)s; }
str ts(str s) { return s; }
str ts(bool b) { 
	#ifdef LOCAL
		return b ? "true" : "false"; 
	#else 
		return ts((int)b);
	#endif
}
tcT> str ts(complex<T> c) { 
	stringstream ss; ss << c; return ss.str(); }
str ts(vector<bool> v) {
	str res = "{"; F0R(i,sz(v)) res += char('0'+v[i]);
	res += "}"; return res; }
template<size_t SZ> str ts(bitset<SZ> b) {
	str res = ""; F0R(i,SZ) res += char('0'+b[i]);
	return res; }
tcTU> str ts(pair<T,U> p);
tcT> str ts(T v) { // containers with begin(), end()
	#ifdef LOCAL
		bool fst = 1; str res = "{";
		for (const auto& x: v) {
			if (!fst) res += ", ";
			fst = 0; res += ts(x);
		}
		res += "}"; return res;
	#else
		bool fst = 1; str res = "";
		for (const auto& x: v) {
			if (!fst) res += " ";
			fst = 0; res += ts(x);
		}
		return res;

	#endif
}
tcTU> str ts(pair<T,U> p) {
	#ifdef LOCAL
		return "("+ts(p.f)+", "+ts(p.s)+")"; 
	#else
		return ts(p.f)+" "+ts(p.s);
	#endif
}

// OUTPUT
tcT> void pr(T x) { cout << ts(x); }
tcTUU> void pr(const T& t, const U&... u) { 
	pr(t); pr(u...); }
void ps() { pr("\n"); } // print w/ spaces
tcTUU> void ps(const T& t, const U&... u) { 
	pr(t); if (sizeof...(u)) pr(" "); ps(u...); }

// DEBUG
void DBG() { cerr << "]" << endl; }
tcTUU> void DBG(const T& t, const U&... u) {
	cerr << ts(t); if (sizeof...(u)) cerr << ", ";
	DBG(u...); }
#ifdef LOCAL // compile with -DLOCAL, chk -> fake assert
	#define dbg(...) cerr << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
	#define chk(...) if (!(__VA_ARGS__)) cerr << "Line(" << __LINE__ << ") -> function(" \
		 << __FUNCTION__  << ") -> CHK FAILED: (" << #__VA_ARGS__ << ")" << "\n", exit(0);
#else
	#define dbg(...) 0
	#define chk(...) 0
#endif

// FILE I/O
void setIn(str s) { freopen(s.c_str(),"r",stdin); }
void setOut(str s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
void setIO(str s = "") {
	unsyncIO();
	// cin.exceptions(cin.failbit); 
	// throws exception when do smth illegal
	// ex. try to read letter into int
	if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
}

bool cmp(pair<int,int> x,pair<int,int> y){
		int d = x.f - x.s;
		int d2 = y.f - y.s;
		if(d > d2) return 1;
		if(d < d2) return 0;
		return (x.f > y.f);
}

bool comp2(pair<int,int> x,pair<int,int> y){
		int d = x.s - x.f;
		int d2 = y.s - y.f;
		if(d > d2) return 1;
		if(d < d2) return 0;
		return (x.s > y.s);
}
signed main() {
	setIO();	
	int n,m,s;
	cin >> n >> m >> s;
	pair<int,int> a[n+1];
	int pre[n+1],suf[n+3];
	for(int i = 1;i <= n;i++){
		cin >> a[i].first >> a[i].second;
	}
	
	sort(a+1,a+n+1,cmp);
	
	int sum = 0;
	pre[0] = 0;
	priority_queue<int,vector<int>,greater<int>> pq;
	for(int i =1;i<=m;i++){
		sum += a[i].f;
		pq.push(a[i].f);
		pre[i] = max(pre[i-1],sum);
	}
	for(int i = m+1;i<=n;i++){
		if(a[i].f > pq.top()){
			sum -= pq.top();
			pq.pop();
			sum += a[i].f;
			pq.push(a[i].f);
		}
		pre[i] = max(pre[i-1],sum);
	}
	while(!pq.empty())pq.pop();
	sum = 0;
	suf[n+1] = 0;
	for(int i =n;i>=1;i--){
		if(pq.size() < s){
			sum += a[i].s;
			pq.push(a[i].s);
			suf[i] = max(suf[i+1],sum);
		}
		else{
			if(a[i].s > pq.top()){
				sum -= pq.top();
				pq.pop();
				sum += a[i].s;
				pq.push(a[i].s);
			}
			suf[i] = max(suf[i+1],sum);
		}
	}
	int ans = 0;
	for(int i = m;i<=n;i++){
		if((n-i) >= s)
			ans = max(ans,pre[i]+suf[i+1]);
	}
	cout<<ans<<endl;
	// int ans = 0;
	// for(int i = 1;i <= m;i++){
	// 	ans += a[i].f;
	// }
	// cout<<"===\n";
	// for(int i=1;i<=n;i++){
	// 	cout << a[i].f << " " << a[i].s << endl;
	// }

	// sort(a+1,a+n+1,comp2);
	// for(int i = 1;i <= s;i++){
	// 	ans += a[i].s;
	// }

	// // for(int i=1;i<=n;i++){
	// // 	cout << a[i].f << " " << a[i].s << endl;
	// // }
	// cout << ans << endl;
	// you should actually read the stuff at the bottom
}

/* stuff you should look for
	* read the probem 3 more times in case of WA :)
	* int overflow, array bounds
	* special cases (n=1?)
	* do smth instead of nothing and stay organized
	* WRITE STUFF DOWN
	* DON'T GET STUCK ON ONE APPROACH
*/

Compilation message

school.cpp: In function 'int main()':
school.cpp:241:16: warning: comparison of integer expressions of different signedness: 'std::priority_queue<long long int, std::vector<long long int>, std::greater<long long int> >::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
  241 |   if(pq.size() < s){
      |                ^
school.cpp: In function 'void setIn(str)':
school.cpp:182:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  182 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
school.cpp: In function 'void setOut(str)':
school.cpp:183:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  183 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 2 ms 512 KB Output is correct
8 Correct 3 ms 640 KB Output is correct
9 Correct 2 ms 512 KB Output is correct
10 Correct 2 ms 512 KB Output is correct
11 Correct 2 ms 640 KB Output is correct
12 Correct 2 ms 512 KB Output is correct
13 Correct 18 ms 1792 KB Output is correct
14 Correct 31 ms 3064 KB Output is correct
15 Correct 57 ms 5368 KB Output is correct
16 Correct 75 ms 7792 KB Output is correct
17 Correct 97 ms 8176 KB Output is correct
18 Correct 107 ms 8812 KB Output is correct
19 Correct 115 ms 9324 KB Output is correct
20 Correct 130 ms 10736 KB Output is correct