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Day 6 solutions

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Peter 2021-12-06 22:10:58 +08:00
parent e547d91e82
commit 1f3169bc83
4 changed files with 250 additions and 0 deletions
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1
.gitignore vendored
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*.out
*.swp
.vscode/
.gdb_history

90
6/6-1.c Normal file
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#include <stdlib.h>
#include <stdio.h>
#include "../check_alloc.h"
#define CYCLE 6
#define STARTING_TIMER 8
unsigned int INITIAL_CONDITION[] = {3, 4, 3, 1, 2};
// LIST DATASTRUCTURE
#define INITIAL_SIZE 20
typedef struct
{
unsigned int *list;
size_t size;
size_t capacity;
} LIST;
void free_list(LIST *list)
{
free(list->list);
free(list);
}
LIST *new_list(void)
{
LIST *p_list = calloc(1, sizeof(LIST));
p_list->capacity = INITIAL_SIZE;
p_list->list = calloc(p_list->capacity, sizeof(unsigned int));
return p_list;
}
void add_list(LIST *list, unsigned int elem)
{
if (list->size >= list->capacity)
{
list->capacity *= 2;
list->list = realloc(list->list, list->capacity * sizeof(unsigned int));
CHECK_ALLOC(list->list);
}
list->list[list->size] = elem;
list->size++;
}
void print_list(LIST *list)
{
for (size_t i = 0; i < list->size; i++)
{
printf("%d ", list->list[i]);
}
putchar('\n');
}
//
void step_time(LIST *state)
{
size_t size_before = state->size;
for (size_t i = 0; i < size_before; i++)
{
if (state->list[i] == 0)
{
state->list[i] = CYCLE;
add_list(state, STARTING_TIMER);
}
else
{
state->list[i]--;
}
}
}
int main(int argc, char const *argv[])
{
LIST *state = new_list();
size_t ic_size = sizeof(INITIAL_CONDITION) / sizeof(INITIAL_CONDITION[0]);
for (size_t i = 0; i < ic_size; i++)
{
add_list(state, INITIAL_CONDITION[i]);
}
for (size_t i = 0; i < 80; i++)
{
step_time(state);
printf("%lu\t", i);
fflush(stdout);
// print_list(state);
}
printf("\n%lu\n", state->size);
return 0;
}

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6/6-2.c Normal file
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#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
// IC
#define TIMESPAN_DAYS 256
unsigned long INITIAL_CONDITION[] = {3, 4, 3, 1, 2};
int main(int argc, char const *argv[])
{
// IC LOGIC
bool is_ic_done = false;
size_t ic_done_count = 0;
size_t ic_size = sizeof(INITIAL_CONDITION) / sizeof(INITIAL_CONDITION[0]);
// Had to scratch this one out on paper to figure it out.
unsigned long cycles7[7] = {0};
unsigned long cycles9[9] = {0};
unsigned long total = 0;
for (size_t t = 0; t < TIMESPAN_DAYS; t++)
{
// APPLY IC BY ADDING TO CYCLES AT OFFSETS SPECIFIED IN ICS
if (!is_ic_done)
{
for (size_t i = 0; i < ic_size; i++)
{
if (t == INITIAL_CONDITION[i])
{
cycles9[t % 9]++;
total++;
ic_done_count++;
}
}
if (ic_done_count > ic_size)
is_ic_done = true;
}
// UPDATE POPULATION
unsigned long v = cycles7[t % 7];
total += cycles9[t % 9];
total += v;
cycles7[t % 7] += cycles9[t % 9];
cycles9[t % 9] += v;
}
printf("%lu\n", total);
return 0;
}

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6/6-2ridiculous_threads.c Normal file
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#include <stdlib.h>
#include <stdio.h>
#include "../check_alloc.h"
#include <pthread.h>
// EXTENDING THE DUMB SOLUTION WITH THREADS - STILL BAD BECAUSE OF THE ALGORITHM'S BAD TIME COMPLEXITY.
#define CYCLE 6
#define STARTING_TIMER 8
unsigned int INITIAL_CONDITION[] = {3, 4, 3, 1, 2};
// LIST DATASTRUCTURE
#define INITIAL_SIZE 20
typedef struct
{
unsigned int *list;
size_t size;
size_t capacity;
} LIST;
void free_list(LIST *list)
{
free(list->list);
free(list);
}
LIST *new_list(void)
{
LIST *p_list = calloc(1, sizeof(LIST));
p_list->capacity = INITIAL_SIZE;
p_list->list = calloc(p_list->capacity, sizeof(unsigned int));
return p_list;
}
void add_list(LIST *list, unsigned int elem)
{
if (list->size >= list->capacity)
{
list->capacity *= 2;
list->list = realloc(list->list, list->capacity * sizeof(unsigned int));
CHECK_ALLOC(list->list);
}
list->list[list->size] = elem;
list->size++;
}
void print_list(LIST *list)
{
for (size_t i = 0; i < list->size; i++)
{
printf("%d ", list->list[i]);
}
putchar('\n');
}
//
void step_time(LIST *state)
{
size_t size_before = state->size;
for (size_t i = 0; i < size_before; i++)
{
if (state->list[i] == 0)
{
state->list[i] = CYCLE;
add_list(state, STARTING_TIMER);
}
else
{
state->list[i]--;
}
}
}
void *manage_part(void *args)
{
LIST *state = (LIST *)args;
for (size_t i = 0; i < 256; i++)
{
step_time(state);
printf("%lu\t", i);
fflush(stdout);
// print_list(state);
}
}
int main(int argc, char const *argv[])
{
size_t ic_size = sizeof(INITIAL_CONDITION) / sizeof(INITIAL_CONDITION[0]);
LIST *parts[ic_size];
pthread_t threads[ic_size];
// MAKE THREADS AND STATE PARTS
for (size_t i = 0; i < ic_size; i++)
{
parts[i] = new_list();
add_list(parts[i], INITIAL_CONDITION[i]);
pthread_create(&threads[i], NULL, manage_part, parts[i]);
}
size_t total = 0;
for (size_t i = 0; i < ic_size; i++)
{
pthread_join(threads[i], NULL);
total += parts[i]->size;
}
printf("\n%lu\n", total);
return 0;
}