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authorJulian T <julian@jtle.dk>2020-02-11 12:24:56 +0100
committerJulian T <julian@jtle.dk>2020-02-11 12:24:56 +0100
commit6db1a2cdd3b96731f2e092d55d8c2136eabc52d0 (patch)
tree2be8fae8ce82d708ed9f00f376dda14420850e80 /sem1/algo/workshop2/dijkstra
parent57305119e05559c1c37e903aef89cd43f44c42c9 (diff)
Rename and cleanup
Diffstat (limited to 'sem1/algo/workshop2/dijkstra')
-rw-r--r--sem1/algo/workshop2/dijkstra/Makefile31
-rw-r--r--sem1/algo/workshop2/dijkstra/dijkstra.c120
-rw-r--r--sem1/algo/workshop2/dijkstra/graph.c215
-rw-r--r--sem1/algo/workshop2/dijkstra/graph.h47
4 files changed, 0 insertions, 413 deletions
diff --git a/sem1/algo/workshop2/dijkstra/Makefile b/sem1/algo/workshop2/dijkstra/Makefile
deleted file mode 100644
index 7837354..0000000
--- a/sem1/algo/workshop2/dijkstra/Makefile
+++ /dev/null
@@ -1,31 +0,0 @@
-CC = gcc
-# Enable gdb and pull include files from current dir
-CFLAGS = -ggdb -I.
-LDFLAGS =
-
-BINARY = dijkstra
-BUILD_DIR = build
-
-# Capture c files
-c_files = $(wildcard *.c)
-
-# Convert c names to corrosponding o names
-OBJ = $(patsubst %.c, $(BUILD_DIR)/%.o, $(c_files))
-
-# $@ is the %.o file and $^ is the %.c file
-$(BUILD_DIR)/%.o: %.c
- mkdir -p $(dir $@)
- $(CC) -c -o $@ $^ $(CFLAGS)
-
-# $@ becomes left part thus linked
-$(BINARY): $(OBJ)
- $(CC) -o $@ $^ $(LDFLAGS)
-
-.PHONY: clean run
-
-run: $(BINARY)
- ./$(BINARY)
-
-clean:
- rm -f $(OBJ) $(BINARY)
- rmdir $(BUILD_DIR)
diff --git a/sem1/algo/workshop2/dijkstra/dijkstra.c b/sem1/algo/workshop2/dijkstra/dijkstra.c
deleted file mode 100644
index 555a125..0000000
--- a/sem1/algo/workshop2/dijkstra/dijkstra.c
+++ /dev/null
@@ -1,120 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include "graph.h"
-
-typedef struct list_item {
- vertex_t *v;
- struct list_item *next;
- struct list_item *prev;
-} list_item_t;
-
-typedef struct {
- int len;
- struct list_item *begin;
- struct list_item *end;
-} list_t;
-
-void list_push(list_t *s, vertex_t *v) {
- // Create
- list_item_t *i = malloc(sizeof(list_item_t));
- i->next = NULL;
- i->prev = NULL;
- i->v = v;
-
- // Link
- if( s->len == 0 ) {
- s->begin = i;
- } else {
- s->end->next = i;
- i->prev = s->end;
- }
-
- s->end = i;
- s->len++;
-}
-
-vertex_t *list_pop_smallest(list_t *s) {
- //printf("beginning %s(%d)\n", s->begin->v->ref, s->begin->v->dist);
- list_item_t *smallest = s->begin;
-
- // Search
- list_item_t *i = s->begin;
- while( i ) {
- if( smallest->v->dist == -1 || (i->v->dist != -1 && i->v->dist < smallest->v->dist) ) {
- smallest = i;
- }
- i = i->next;
- }
-
- if( smallest == s->begin ) {
- s->begin = smallest->next;
- } else {
- smallest->prev->next = smallest->next;
- }
-
- if( smallest == s->end ) {
- s->end = smallest->prev;
- } else {
- smallest->next->prev = smallest->prev;
- }
-
- vertex_t *v = smallest->v;
- free(smallest);
-
- s->len--;
-
- return v;
-}
-
-graph_t g;
-
-// Assumes u has an edge to v
-void relax(vertex_t *u, vertex_t *v) {
- // Get edge between these two guys
- edge_t *e = u->adj;
- while(e && e->next && strcmp(e->to->ref, v->ref)) {
- e = e->next;
- }
-
- if( v->dist == -1 || v->dist > (u->dist + e->weight) ) {
- v->dist = u->dist + e->weight;
- v->p = u;
- }
-}
-
-void dijkstra(graph_t *g, vertex_t *s) {
- list_t list;
- list.len = 0;
- list.end = list.begin = 0;
-
- s->dist = 0;
-
- {
- vertex_t *v = vertex_next(g, NULL);
- while( v ) {
- list_push(&list, v);
- v = vertex_next(g, v);
- }
- }
-
- while( list.len ) {
- vertex_t *u = list_pop_smallest(&list);
- edge_t *e = u->adj;
- while( e ) {
- relax(u, e->to );
- e = e->next;
- }
- }
-}
-
-int main() {
-
- graph_from_dot(stdin, &g);
-
- dijkstra(&g, graph_vertex(&g, "0"));
-
- graph_to_dot(stdout, &g);
-
- return 0;
-}
diff --git a/sem1/algo/workshop2/dijkstra/graph.c b/sem1/algo/workshop2/dijkstra/graph.c
deleted file mode 100644
index 8f62981..0000000
--- a/sem1/algo/workshop2/dijkstra/graph.c
+++ /dev/null
@@ -1,215 +0,0 @@
-#include <stdio.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "graph.h"
-
-// Hashtable
-static unsigned int hash(char *s) {
- uint32_t hv = 0;
- for( int i = 0; s[i] != '\0'; i++ ) {
- // take MSB 6 bits of hv and xors with LSB of s[i]
- uint32_t v = ( hv >> 26 ) ^ (s[i] & 0x3f);
-
- // Push those back on hv
- hv = (hv << 4) | v;
- }
- // Return appropriate size
- return hv % HASHSIZE;
-}
-
-
-static void table_insert(graph_t *g, vertex_t *v, char *var) {
- unsigned int index = hash(var);
-
- // Save old value
- vertex_t *oldSym = g->hashtable[index];
-
- // Make new
- g->hashtable[index] = v;
-
- // Link old one
- g->hashtable[index]->next = oldSym;
-}
-
-static vertex_t *table_lookup(graph_t *g, char *var) {
- unsigned int index = hash(var);
- vertex_t *n = g->hashtable[index];
-
- // Look trough list
- while(n != NULL && strcmp(n->ref, var) != 0) {
- n = n->next;
- }
-
- return n;
-}
-
-static vertex_t *create_vertex(char *ref) {
- // Get some space TODO check for null
- vertex_t *v = malloc(sizeof(vertex_t));
-
- // Set values
- v->ref = strdup(ref);
- v->color = COLOR_WHITE;
- v->p = NULL;
- v->dist = -1;
- v->adj = NULL;
- return v;
-}
-
-static edge_t *create_edge(vertex_t *from, vertex_t *to, int weight) {
- edge_t *old = from->adj;
-
- // Create new list node
- edge_t *e = malloc(sizeof(edge_t));
- e->weight = weight;
- e->from = from;
- e->to = to;
-
- // Do new link
- e->next = old;
- if( old ) {
- e->prev = old->prev;
- old->prev = e;
- } else { e->prev = NULL; }
-
- if( e->prev ) {
- e->prev->next = e;
- }
-
- from->adj = e;
-
- return e;
-}
-
-// For iterating edges
-edge_t *edge_next(graph_t *g, edge_t *e) {
- if(e == NULL || e->next == NULL ) {
- // Find next index
- vertex_t *v = e ? e->from : NULL;
-
- // Find next vertex
- v = vertex_next(g, v);
- while( v ) {
- // Check if found
- if( v->adj ) {
- return v->adj;
- }
-
- v = vertex_next(g, v);
- }
-
- // No next vertex
- return NULL;
- }
-
- // Not finished with this adj list
- return e->next;
-}
-
-vertex_t *vertex_next(graph_t *g, vertex_t *v) {
- if( v == NULL || v->next == NULL) {
- // Go to next index in hashtable
- int i = v ? hash(v->ref)+1 : 0;
- for( ; i < HASHSIZE; i++) {
- if( g->hashtable[i] ) {
- return g->hashtable[i];
- }
- }
-
- // No next
- return NULL;
- }
-
- return v->next;
-}
-
-void graph_edge(graph_t *g, char *from, char *to, int weight) {
- vertex_t *fromv, *tov;
- // Does a exists
- if( (fromv = table_lookup(g, from)) == NULL ) {
- fromv = create_vertex(from);
- table_insert(g, fromv, from);
- }
- // What about b
- if( (tov = table_lookup(g, to)) == NULL ) {
- tov = create_vertex(to);
- table_insert(g, tov, to);
- }
-
- // Add edge
- create_edge(fromv, tov, weight);
-}
-
-int graph_print_adj(graph_t *g, char *ref) {
- vertex_t *v = table_lookup(g, ref);
- if( v == NULL ) {
- return 1;
- }
-
- edge_t *e = v->adj;
- printf("[ ");
- while(e && e->from->ref == ref) {
- printf("%s[%d] ", e->to->ref, e->weight);
- e = e->next;
- }
- printf("]\n");
-
- return 0;
-}
-
-int graph_to_dot(FILE *f, graph_t *g) {
- // print pre stuff
- fprintf(f, "digraph coolgraph {\n");
-
- // Label all nodes
- vertex_t *v = vertex_next(g, NULL);
- while( v ) {
- fprintf(f, "%s [label=\"%s(%d)\"];\n", v->ref, v->ref, v->dist);
- v = vertex_next(g, v);
- }
- // Print all the edges
- edge_t *e = edge_next(g, NULL);
- while( e ) {
- fprintf(f, "%s -> %s [label = %d%s];\n", e->from->ref, e->to->ref, e->weight, e->to->p == e->from ? " color=blue" : "");
- e = edge_next(g, e);
- }
-
- // done
- fprintf(f, "}\n");
-}
-
-// This was created in a hurry sorry
-int graph_from_dot(FILE *f, graph_t *g) {
- char from[100], to[100];
- int weight;
- // just fscanf it
- for(;;) {
- // Set first to zero
- *from = 0;
- *to = 0;
- weight = 0;
- int c = fscanf(f, "%s -> %s [label=%d];", from, to, &weight);
- if( c <= 0 ) {
- break;
- }
- if( *from == 0 || *to == 0 ) {
- continue;
- }
- // Sorry i just want it to work
- int tolen = strlen(to);
- if( to[tolen-1] == ';' ) {
- to[tolen-1] = 0;
- }
-
- weight = weight ? weight : 1;
- //printf("Creating edge from %s to %s with w: %d\n", from, to, weight);
-
- graph_edge(g, from, to, weight);
- }
-}
-
-vertex_t *graph_vertex(graph_t *g, char *ref) {
- return table_lookup(g, ref);
-}
diff --git a/sem1/algo/workshop2/dijkstra/graph.h b/sem1/algo/workshop2/dijkstra/graph.h
deleted file mode 100644
index 5c078b8..0000000
--- a/sem1/algo/workshop2/dijkstra/graph.h
+++ /dev/null
@@ -1,47 +0,0 @@
-#ifndef GRAPH_H_
-#define GRAPH_H_
-
-#define COLOR_WHITE 0
-#define COLOR_GRAY 1
-#define COLOR_BLACK 2
-
-#define HASHSIZE 128
-
-struct vertex_struct;
-
-// Linked list
-typedef struct edge_struct {
- int weight;
- struct vertex_struct *from;
- struct vertex_struct *to;
- // Linked list stuff
- struct edge_struct *next;
- struct edge_struct *prev;
-} edge_t;
-
-typedef struct vertex_struct {
- char *ref;
- int color;
-
- int dist;
- struct vertex_struct *p;
-
- edge_t *adj;
-
- // Hash table stuff
- struct vertex_struct *next;
-} vertex_t;
-
-typedef struct {
- vertex_t *hashtable[128];
-} graph_t;
-
-int graph_to_dot(FILE *f, graph_t *g);
-int graph_from_dot(FILE *f, graph_t *g);
-int graph_print_adj(graph_t *g, char *ref);
-void graph_edge(graph_t *g, char *from, char *to, int weight);
-edge_t *edge_next(graph_t *g, edge_t *e);
-vertex_t *vertex_next(graph_t *g, vertex_t *v);
-vertex_t *graph_vertex(graph_t *g, char *ref);
-
-#endif // GRAPH_H_