Cod sursa(job #1694199)

Utilizator sdwolfSDWOLF sdwolf Data 24 aprilie 2016 22:01:59
Problema Sortare prin comparare Scor 20
Compilator c Status done
Runda Arhiva educationala Marime 3.25 kb
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>

void read_input(int **list, int *size);
void flash_sort(int *list, int size);
void hulk_sort(int *list, int low, int high);
void swap_values(int *first, int *second);
int select_pivot(int *list, int low, int high);
void write_output(int *list, int size);

int main() {
  int size;
  int *list;

  srand(time(NULL));

  read_input(&list, &size);
  flash_sort(list, size);
  write_output(list, size);

  return 0;
}

void read_input(int **list, int *size) {
  FILE *input = fopen("algsort.in", "r");

  fscanf(input, "%d\n", size);

  *list = (int*) malloc(sizeof(int) * (*size));

  for (int index = 0; index < *size; index +=1) {
    fscanf(input, "%d", *list + index);
  }

  fclose(input);
}

void flash_sort(int *list, int size) {
  int pivot, pivot_position, sort_threshold;
  int left, left_low, right, right_high;

  int *partition_low, *partition_high;
  int partition_size, partition_start, partition_end;

  partition_size  = 200000;
  partition_low   = (int*) malloc(sizeof(int) * (partition_size));
  partition_high  = (int*) malloc(sizeof(int) * (partition_size));

  sort_threshold = 10;

  left_low   = 0;
  right_high = size -1;

  partition_start = -1;
  partition_end   = 0;

  partition_low[partition_end]  = left_low;
  partition_high[partition_end] = right_high;

  while(partition_start < partition_end) {
    partition_start += 1;

    left_low   = partition_low[partition_start];
    right_high = partition_high[partition_start];

    if (right_high - left_low <= sort_threshold) {
      hulk_sort(list, left_low, right_high);

      continue;
    }

    pivot_position = select_pivot(list, left_low, right_high);

    left  = left_low;
    right = right_high;

    pivot = list[pivot_position];

    while (left <= right) {
      while(list[left]  < pivot && left  < right_high) left  += 1;
      while(list[right] > pivot && right > left_low)   right -= 1;

      if (left <= right) {
        if (list[left] < list[right]) {
          swap_values(&list[left], &list[right]);
        }
        left  += 1;
        right -= 1;
      };
    }

    if (left_low < right) {
      partition_end                 += 1;
      partition_high[partition_end] = right;
      partition_low[partition_end]  = left_low;
    }

    if (left < right_high) {
      partition_end                 += 1;
      partition_high[partition_end] = right_high;
      partition_low[partition_end]  = left;
    }
  }
}

void hulk_sort(int *list, int low, int high) {
  int carry;

  for (int first = low; first < high; first += 1) {
    for (int second = first + 1; second <= high; second += 1) {
      if (list[first] > list[second]) {
        swap_values(&list[first], &list[second]);
      }
    }
  }
}

void swap_values(int *first, int *second) {
  int carry;

  carry   = *first;
  *first  = *second;
  *second = carry;
}

int select_pivot(int *list, int low, int high) {
  return rand() % (high - low) + low;
}

void write_output(int *list, int size) {
  FILE *output = fopen("algsort.out", "w");

  int last = size - 1;

  for (int index = 0; index < size; index +=1) {
    if (index < last) {
      fprintf(output, "%d ", list[index]);
    } else {
      fprintf(output, "%d", list[index]);
    }
  }
  fprintf(output, "\n");

  fclose(output);
}