Submission #538930

#	Time	Username	Problem	Language	Result	Execution time	Memory
538930		ac2hu	Lightning Rod (NOI18_lightningrod)	C++14	4 / 100	380 ms	207748 KiB

Main

#include <bits/stdc++.h>
#ifdef DEBUG
#include "../templates/debug.h"
#else 
#define deb(x...)
#endif
using namespace std;
inline int readChar();
template <class T = long long> inline T readInt(); 
template <class T> inline void writeInt( T x, char end = 0 );
inline void writeChar( int x ); 
inline void writeWord( const char *s );

/** Read */

static const int buf_size = 4096;

inline int getChar() {
    static char buf[buf_size];
    static int len = 0, pos = 0;
    if (pos == len)
        pos = 0, len = fread(buf, 1, buf_size, stdin);
    if (pos == len)
        return -1;
    return buf[pos++];
}

inline int readChar() {
    int c = getChar();
    while (c <= 32)
        c = getChar();
    return c;
}

template <class T>
inline T readInt() {
    int s = 1, c = readChar();
    T x = 0;
    if (c == '-')
        s = -1, c = getChar();
    while ('0' <= c && c <= '9')
        x = x * 10 + c - '0', c = getChar();
    return s == 1 ? x : -x;
}

/** Write */

static int write_pos = 0;
static char write_buf[buf_size];

inline void writeChar( int x ) {
    if (write_pos == buf_size)
        fwrite(write_buf, 1, buf_size, stdout), write_pos = 0;
    write_buf[write_pos++] = x;
}

template <class T> 
inline void writeInt( T x, char end ) {
    if (x < 0)
        writeChar('-'), x = -x;

    char s[24];
    int n = 0;
    while (x || !n)
        s[n++] = '0' + x % 10, x /= 10;
    while (n--)
        writeChar(s[n]);
    if (end)
        writeChar(end);
}

inline void writeWord( const char *s ) {
    while (*s)
        writeChar(*s++);
}

struct Flusher {
    ~Flusher() {
        if (write_pos)
            fwrite(write_buf, 1, write_pos, stdout), write_pos = 0;
    }
} flusher;
signed main() {
	iostream::sync_with_stdio(false);
	cin.tie(nullptr);cout.tie(nullptr);
	int n = readInt();
	vector<pair<int,int>> a(n);
	for(auto &e : a){
		e.first = readInt();
		e.second = readInt();
	}
	auto fit = [&](pair<int,int> a,pair<int,int> b) -> bool{
		// if b can't fit a 
		return (abs(b.first  - a.first) <= abs(b.second - a.second));
	};
	auto better = [&](pair<int,int> a, pair<int,int> b) -> bool{
		if(a.first + a.second > b.first + b.second)
			return true;
		return false;
	};
	vector<pair<int,int>> st;
	st.push_back(a[0]);
	for(int i = 1;i<n;i++){
		while(st.size() > 0 && fit(a[i], st.back()) && better(a[i], st.back()))
			st.pop_back();
		if(!fit(a[i], st.back()) && !better(st.back(), a[i])){
			st.push_back(a[i]);
		}
		// if(st.size() > 0 && fit(a[i], st.top()) && ){
		// }
		// else{
			// while(st.size() > 0 && fit(a[]))
		// }
		deb(st);
	}
	cout << st.size() << "\n";
}

• Subtask 1: 4 / 4
• Subtask 2: 0 / 7
• Subtask 3: 0 / 12
• Subtask 4: 0 / 21
• Subtask 5: 0 / 26
• Subtask 6: 0 / 10
• Subtask 7: 0 / 20