Cod sursa(job #1938644)

Utilizator radu.leonardoThe Doctor radu.leonardo Data 24 martie 2017 22:51:32
Problema Sortare prin comparare Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 2.34 kb
#include <bits/stdc++.h>
#define Bucket_size 8
using namespace std;

class Reader
{
public:
    Reader() {}
    Reader(const char *file_name)
    {
        input_file = fopen(file_name, "r");
        cursor = 0;
        fread(buffer, SIZE, 1, input_file);
    }
    inline Reader &operator >>(int &n)
    {
        while(buffer[cursor] < '0' || buffer[cursor] > '9')
        {
            advance();
        }
        n = 0;
        while('0' <= buffer[cursor] && buffer[cursor] <= '9')
        {
            n = n * 10 + buffer[cursor] - '0';
            advance();
        }
        return *this;
    }
private:
    FILE *input_file;
    static const int SIZE = 1 << 17;
    int cursor;
    char buffer[SIZE];
    inline void advance()
    {
        ++ cursor;
        if(cursor == SIZE)
        {
            cursor = 0;
            fread(buffer, SIZE, 1, input_file);
        }
    }
};

class Writer
{
public:
    Writer(const char *name):
        m_stream(name)
    {
        memset(m_buffer, 0, sizeof(m_buffer));
        m_pos = 0;
    }

    Writer& operator<<(int a)
    {
        int many = 0;
        do
        {
            digit_buffer[many++] = a % 10 + '0';
            a /= 10;
        }
        while (a > 0);
        for (int i = many - 1; i >= 0; --i)
            putchar(digit_buffer[i]);
        return *this;
    }

    Writer& operator<<(const char *s)
    {
        for (; *s; ++s)
            putchar(*s);
        return *this;
    }

    ~Writer()
    {
        m_stream.write(m_buffer, m_pos);
    }

private:
    void putchar(char c)
    {
        m_buffer[m_pos++] = c;
        if (m_pos == kBufferSize)
        {
            m_stream.write(m_buffer, m_pos);
            m_pos = 0;
        }
    }

    static const int kBufferSize = 1 << 17;
    ofstream m_stream;
    char m_buffer[kBufferSize];
    char digit_buffer[30];
    int m_pos;
};

Reader f ("algsort.in");
Writer g ("algsort.out");

int n;
vector <unsigned int> V;

void radixsort(int bits)
{
    vector <unsigned int> Sorted_Bucket[(1<<Bucket_size)];

    for(auto it:V)  Sorted_Bucket[(it>>bits)&((1<<Bucket_size)-1)].push_back(it);

    for(int i=0,n=0; i<(1<<Bucket_size); ++i)
        for(auto it:Sorted_Bucket[i]) V[n++]=it;
}

int main()
{
    int x;
    f>>n;
    for(int i=0; i<n; ++i)   f>>x,V.push_back(x);
    for(int i=0; i<32; i+=Bucket_size) radixsort(i);
    for(auto it:V) g<<it<<" ";
}