Submission #1036603

#	Time	Username	Problem	Language	Result	Execution time	Memory
1036603		Nonoze	Mobile (BOI12_mobile)	C++17	100 / 100	217 ms	35600 KiB

mobile

#include <bits/stdc++.h>
#define sz(x) (int)(x.size())
using namespace std;

inline namespace IO {
    const int BUFFER_SIZE = 1 << 15;
 
    char input_buffer[BUFFER_SIZE];
    int input_pos = 0, input_len = 0;
 
    char output_buffer[BUFFER_SIZE];
    int output_pos = 0;
 
    char number_buffer[100];
    uint8_t lookup[100];
 
    void _update_input_buffer() {
        input_len = fread(input_buffer, sizeof(char), BUFFER_SIZE, stdin);
        input_pos = 0;
 
        if (input_len == 0)
            input_buffer[0] = EOF;
    }
 
    inline char next_char(bool advance = true) {
        if (input_pos >= input_len)
            _update_input_buffer();
 
        return input_buffer[advance ? input_pos++ : input_pos];
    }
 
    template<typename T> 
    inline void read_int(T &number) {
        bool negative = false;
        number = 0;
 
        while (!isdigit(next_char(false)))
            if (next_char() == '-')
                negative = true;
 
        do {
            number = 10 * number + (next_char() - '0');
        } while (isdigit(next_char(false)));
 
        if (negative)
            number = -number;
    }
 
    template<typename T, typename... Args> 
    inline void read_int(T &number, Args &... args) {
        read_int(number);
        read_int(args...);
    }
 
    void _flush_output() {
        fwrite(output_buffer, sizeof(char), output_pos, stdout);
        output_pos = 0;
    }
 
    inline void write_char(char c) {
        if (output_pos == BUFFER_SIZE)
            _flush_output();
 
        output_buffer[output_pos++] = c;
    }
 
    template<typename T>
    inline void write_int(T number, char after = '\0') {
        if (number < 0) {
            write_char('-');
            number = -number;
        }
 
        int length = 0;
 
        while (number >= 10) {
            uint8_t lookup_value = lookup[number % 100];
            number /= 100;
            number_buffer[length++] = (lookup_value & 15) + '0';
            number_buffer[length++] = (lookup_value >> 4) + '0';
        }
 
        if (number != 0 || length == 0)
            write_char(number + '0');
 
        for (int i = length - 1; i >= 0; i--)
            write_char(number_buffer[i]);
 
        if (after)
            write_char(after);
    }
 
    void init() {
        // Make sure _flush_output() is called at the end of the program.
        bool exit_success = atexit(_flush_output) == 0;
        assert(exit_success);
 
        for (int i = 0; i < 100; i++)
            lookup[i] = (i / 10 << 4) + i % 10;
    }
}
 
int n, L;
vector<pair<double, double>> a;
 
void solve() {
	read_int(n, L);
	a.clear();
	for (int i=0; i<n; i++) {
		int x, y; read_int(x, y);
		if (!a.empty() && x==a.back().first) {
			if (abs(y)<abs(a.back().second)) a.back().second=y;
		}
		else a.push_back({x, y});
	}
	n=sz(a);
	double l=0, r=1e9;
	while (r-l>0.0009) {
		double mid=(l+r)/2;
		double borne=0;
		double popo=pow(mid, 2);
		for (int i=0; i<n; i++) {
			if (abs(a[i].second)>mid) continue;
			double x=a[i].first, y=a[i].second;
			double dist=sqrt(popo-pow(y, 2));
			if (x-dist<=borne && x+dist>borne) borne=x+dist;
		}
		if (borne>=L) r=mid;
		else l=mid;
	}
	cout << fixed << setprecision(3) << l << '\n';
	return;
}
 
 
signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	solve();
	return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 4 / 4
• Subtask 3: 4 / 4
• Subtask 4: 4 / 4
• Subtask 5: 4 / 4
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
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• Subtask 10: 5 / 5
• Subtask 11: 5 / 5
• Subtask 12: 5 / 5
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• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
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• Subtask 19: 5 / 5
• Subtask 20: 5 / 5
• Subtask 21: 5 / 5