Submission #329360

# Submission time Handle Problem Language Result Execution time Memory
329360 2020-11-20T19:29:49 Z rqi Mecho (IOI09_mecho) C++14
66 / 100
1000 ms 7404 KB
#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef double db; 
typedef string str; 

typedef pair<int,int> pi;
typedef pair<ll,ll> pl; 
typedef pair<db,db> pd; 

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

#define mp make_pair
#define f first
#define s second
#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 

#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; 
const ld PI = acos((ld)-1);
const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1}; 
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 

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; } 
constexpr int pct(int x) { return __builtin_popcount(x); } 
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
ll half(ll x) { return fdiv(x,2); }

template<class T, class U> T fstTrue(T lo, T hi, U f) { 
	// note: if (lo+hi)/2 is used instead of half(lo+hi) then this will loop infinitely when lo=hi
	hi ++; assert(lo <= hi); // assuming f is increasing
	while (lo < hi) { // find first index such that f is true 
		T mid = half(lo+hi);
		f(mid) ? hi = mid : lo = mid+1; 
	} 
	return lo;
}
template<class T, class U> 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 = half(lo+hi+1);
		f(mid) ? lo = mid : hi = mid-1;
	} 
	return lo;
}
template<class T> void remDup(vector<T>& v) { 
	sort(all(v)); v.erase(unique(all(v)),end(v)); }

// INPUT
template<class A> void re(complex<A>& c);
template<class A, class B> void re(pair<A,B>& p);
template<class A> void re(vector<A>& v);
template<class A, size_t SZ> void re(array<A,SZ>& a);

template<class T> 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); }
template<class H, class... T> void re(H& h, T&... t) { re(h); re(t...); }

template<class A> void re(complex<A>& c) { A a,b; re(a,b); c = {a,b}; }
template<class A, class B> void re(pair<A,B>& p) { re(p.f,p.s); }
template<class A> void re(vector<A>& x) { trav(a,x) re(a); }
template<class A, size_t SZ> void re(array<A,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
}
template<class A> str ts(complex<A> 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; }
template<class A, class B> str ts(pair<A,B> p);
template<class T> 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
}
template<class A, class B> str ts(pair<A,B> p) {
	#ifdef LOCAL
		return "("+ts(p.f)+", "+ts(p.s)+")"; 
	#else
		return ts(p.f)+" "+ts(p.s);
	#endif
}

// OUTPUT
template<class A> void pr(A x) { cout << ts(x); }
template<class H, class... T> void pr(const H& h, const T&... t) { 
	pr(h); pr(t...); }
void ps() { pr("\n"); } // print w/ spaces
template<class H, class... T> void ps(const H& h, const T&... t) { 
	pr(h); if (sizeof...(t)) pr(" "); ps(t...); }

// DEBUG
void DBG() { cerr << "]" << endl; }
template<class H, class... T> void DBG(H h, T... t) {
	cerr << ts(h); if (sizeof...(t)) cerr << ", ";
	DBG(t...); }
#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
}

const int mx = 805;
int N, S;
bool bearclose[mx][mx]; //closed to the bear
bool beeclose[mx][mx];
vpi hives;
pi pstart, pend;
int bdist[mx][mx];

void genBeeDists(){
	for(int i = 1; i <= N; i++){
		for(int j = 1; j <= N; j++){
			bdist[i][j] = MOD;
		}
	}

	queue<pair<int, pi>> q;

	for(auto u: hives){
		bdist[u.f][u.s] = 0;
		q.push(mp(0, u));
	}

	while(sz(q)){
		int dist = q.front().f;
		pi pos = q.front().s;
		q.pop();
		for(int d = 0; d < 4; d++){
			if(beeclose[pos.f+xd[d]][pos.s+yd[d]]) continue;
			if(bdist[pos.f+xd[d]][pos.s+yd[d]] <= dist+1) continue;
			bdist[pos.f+xd[d]][pos.s+yd[d]] = dist+1;
			q.push(mp(dist+1, mp(pos.f+xd[d], pos.s+yd[d])));
		}
	}

}

int ctim[mx][mx];

bool works(ll wait){

	for(int i = 1; i <= N; i++){
		for(int j = 1; j <= N; j++){
			ctim[i][j] = MOD;
		}
	}

	queue<pair<ll, pi>> q;
	if(wait*S >= ll(S)*ll(bdist[pstart.f][pstart.s])) return 0;
	q.push(mp(wait*S, pstart));

	while(sz(q)){
		ll dist = q.front().f;
		pi pos = q.front().s;
		q.pop();
		// if(wait == 2){
		// 	dbg(pos);
		// }
		if(pos == pend) return 1;

		for(int d = 0; d < 4; d++){
			if(bearclose[pos.f+xd[d]][pos.s+yd[d]]) continue;
			if(ctim[pos.f+xd[d]][pos.s+yd[d]] <= dist+1) continue;
			if(dist+1 >= ll(S)*ll(bdist[pos.f+xd[d]][pos.s+yd[d]])) continue;
			ctim[pos.f+xd[d]][pos.s+yd[d]] = dist+1;
			q.push(mp(dist+1, mp(pos.f+xd[d], pos.s+yd[d])));
		}
	}

	return 0;
}

int main() {
	setIO();
	cin >> N >> S;
	//assert(N <= 60);
	
	for(int i = 1; i <= N; i++){
		string s;
		cin >> s;
		for(int j = 0; j < N; j++){
			if(s[j] == 'T'){
				bearclose[i][j+1] = 1;
				beeclose[i][j+1] = 1;
			}
			else if(s[j] == 'G'){

			}
			else if(s[j] == 'M'){
				pstart = mp(i, j+1);
			}
			else if(s[j] == 'D'){
				beeclose[i][j+1] = 1;
				pend = mp(i, j+1);
			}
			else if(s[j] == 'H'){
				bearclose[i][j+1] = 1;
				hives.pb(mp(i, j+1));
			}
		}
	}

	for(int i = 0; i <= N+1; i++){
		bearclose[i][0] = 1;
		bearclose[i][N+1] = 1;
		bearclose[0][i] = 1;
		bearclose[N+1][i] = 1;
		beeclose[i][0] = 1;
		beeclose[i][N+1] = 1;
		beeclose[0][i] = 1;
		beeclose[N+1][i] = 1;
	}

	genBeeDists();

	// for(int i = 1; i <= N; i++){
	// 	for(int j = 1; j <= N; j++){
	// 		cout << bdist[i][j] << " ";
	// 	}
	// 	cout << "\n";
	// }

	int lo = -1;
	int hi = mx*mx;

	while(lo < hi){
		int mid = (lo+hi)/2+1;
		if(works(mid)){
			lo = mid;
		}
		else hi = mid-1;
	}

	ps(lo);

	// you should actually read the stuff at the bottom
}

/* stuff you should look for
	* int overflow, array bounds
	* special cases (n=1?)
	* do smth instead of nothing and stay organized
	* WRITE STUFF DOWN
*/

Compilation message

mecho.cpp: In function 'void setIn(str)':
mecho.cpp:168:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  168 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
mecho.cpp: In function 'void setOut(str)':
mecho.cpp:169:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  169 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Correct 1 ms 364 KB Output is correct
4 Correct 1 ms 364 KB Output is correct
5 Execution timed out 1090 ms 364 KB Time limit exceeded
6 Correct 1 ms 492 KB Output is correct
7 Correct 112 ms 7404 KB Output is correct
8 Execution timed out 1092 ms 492 KB Time limit exceeded
9 Correct 1 ms 492 KB Output is correct
10 Correct 1 ms 492 KB Output is correct
11 Correct 1 ms 492 KB Output is correct
12 Correct 1 ms 876 KB Output is correct
13 Execution timed out 1093 ms 748 KB Time limit exceeded
14 Execution timed out 1078 ms 876 KB Time limit exceeded
15 Correct 1 ms 492 KB Output is correct
16 Correct 1 ms 492 KB Output is correct
17 Correct 1 ms 492 KB Output is correct
18 Correct 1 ms 620 KB Output is correct
19 Correct 1 ms 620 KB Output is correct
20 Correct 1 ms 620 KB Output is correct
21 Correct 1 ms 620 KB Output is correct
22 Correct 1 ms 620 KB Output is correct
23 Correct 1 ms 748 KB Output is correct
24 Correct 1 ms 748 KB Output is correct
25 Correct 1 ms 876 KB Output is correct
26 Correct 1 ms 876 KB Output is correct
27 Correct 1 ms 876 KB Output is correct
28 Correct 1 ms 876 KB Output is correct
29 Correct 1 ms 876 KB Output is correct
30 Correct 1 ms 876 KB Output is correct
31 Correct 1 ms 1004 KB Output is correct
32 Correct 1 ms 1004 KB Output is correct
33 Correct 6 ms 3180 KB Output is correct
34 Correct 7 ms 3180 KB Output is correct
35 Correct 29 ms 3308 KB Output is correct
36 Correct 8 ms 3712 KB Output is correct
37 Correct 8 ms 3692 KB Output is correct
38 Correct 35 ms 3692 KB Output is correct
39 Correct 9 ms 4076 KB Output is correct
40 Correct 10 ms 4076 KB Output is correct
41 Correct 44 ms 4076 KB Output is correct
42 Correct 11 ms 4608 KB Output is correct
43 Correct 12 ms 4588 KB Output is correct
44 Correct 55 ms 4588 KB Output is correct
45 Correct 14 ms 4972 KB Output is correct
46 Correct 14 ms 4972 KB Output is correct
47 Correct 67 ms 4972 KB Output is correct
48 Correct 16 ms 5484 KB Output is correct
49 Correct 15 ms 5484 KB Output is correct
50 Correct 84 ms 5612 KB Output is correct
51 Correct 19 ms 5868 KB Output is correct
52 Correct 18 ms 5868 KB Output is correct
53 Correct 103 ms 5868 KB Output is correct
54 Correct 20 ms 5868 KB Output is correct
55 Correct 20 ms 5868 KB Output is correct
56 Correct 116 ms 5868 KB Output is correct
57 Correct 23 ms 6252 KB Output is correct
58 Correct 24 ms 6252 KB Output is correct
59 Correct 138 ms 6252 KB Output is correct
60 Correct 25 ms 6636 KB Output is correct
61 Correct 26 ms 6636 KB Output is correct
62 Correct 168 ms 6764 KB Output is correct
63 Execution timed out 1084 ms 6636 KB Time limit exceeded
64 Correct 196 ms 6764 KB Output is correct
65 Correct 181 ms 6764 KB Output is correct
66 Correct 133 ms 6636 KB Output is correct
67 Execution timed out 1097 ms 6636 KB Time limit exceeded
68 Execution timed out 1093 ms 6764 KB Time limit exceeded
69 Correct 56 ms 6764 KB Output is correct
70 Correct 55 ms 6764 KB Output is correct
71 Correct 51 ms 6764 KB Output is correct
72 Correct 42 ms 6892 KB Output is correct
73 Correct 50 ms 7148 KB Output is correct
74 Correct 71 ms 7148 KB Output is correct
75 Correct 82 ms 7148 KB Output is correct
76 Correct 77 ms 7128 KB Output is correct
77 Correct 78 ms 7148 KB Output is correct
78 Execution timed out 1097 ms 7020 KB Time limit exceeded
79 Correct 74 ms 7020 KB Output is correct
80 Correct 81 ms 7020 KB Output is correct
81 Correct 94 ms 7020 KB Output is correct
82 Correct 74 ms 7148 KB Output is correct
83 Execution timed out 1088 ms 7020 KB Time limit exceeded
84 Correct 85 ms 7136 KB Output is correct
85 Correct 84 ms 7148 KB Output is correct
86 Correct 89 ms 7020 KB Output is correct
87 Correct 89 ms 7020 KB Output is correct
88 Execution timed out 1095 ms 7020 KB Time limit exceeded
89 Correct 94 ms 6892 KB Output is correct
90 Correct 98 ms 6892 KB Output is correct
91 Correct 103 ms 6892 KB Output is correct
92 Correct 96 ms 6892 KB Output is correct