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| author | Thomas Schmucker <ts@its1.de> | 2020-08-14 17:55:16 +0200 |
|---|---|---|
| committer | Thomas Schmucker <ts@its1.de> | 2020-08-14 17:55:16 +0200 |
| commit | 1e6334eaa1ae4423061cea0455b08d6e096001f3 (patch) | |
| tree | 5b16f42fe2ee8fdb69b18c38f4eb6bac190156d0 | |
| parent | 9990de5ea16ed1f6c6df647a9dd43f7c4f5f2653 (diff) | |
| download | data-structures-1e6334eaa1ae4423061cea0455b08d6e096001f3.tar.gz data-structures-1e6334eaa1ae4423061cea0455b08d6e096001f3.tar.bz2 data-structures-1e6334eaa1ae4423061cea0455b08d6e096001f3.zip | |
Verwende etwas sprechendere Namen...
| -rw-r--r-- | deque.c | 102 |
1 files changed, 51 insertions, 51 deletions
| @@ -12,28 +12,28 @@ typedef int T; | |||
| 12 | struct deque { | 12 | struct deque { |
| 13 | T **map; | 13 | T **map; |
| 14 | 14 | ||
| 15 | size_t first_chunk; | 15 | size_t map_begin; |
| 16 | size_t last_chunk; | 16 | size_t map_end; |
| 17 | size_t map_capacity; | ||
| 17 | 18 | ||
| 18 | size_t start; | 19 | size_t offset; |
| 19 | size_t size; | 20 | size_t size; |
| 20 | size_t capacity; | ||
| 21 | }; | 21 | }; |
| 22 | 22 | ||
| 23 | void | 23 | void |
| 24 | deque_init(struct deque *d) | 24 | deque_init(struct deque *d) |
| 25 | { | 25 | { |
| 26 | d->first_chunk = 0; | 26 | d->map_begin = 0; |
| 27 | d->last_chunk = 0; | 27 | d->map_end = 0; |
| 28 | d->start = 0; | 28 | d->offset = 0; |
| 29 | d->size = 0; | 29 | d->size = 0; |
| 30 | 30 | ||
| 31 | // TODO: Error handling | 31 | // TODO: Error handling |
| 32 | d->map = calloc(START_MAP_CAPACITY, sizeof *d->map); | 32 | d->map = calloc(START_MAP_CAPACITY, sizeof *d->map); |
| 33 | if ( d->map != NULL ) { | 33 | if ( d->map != NULL ) { |
| 34 | d->capacity = START_MAP_CAPACITY; | 34 | d->map_capacity = START_MAP_CAPACITY; |
| 35 | 35 | ||
| 36 | for ( size_t i = 0; i != d->capacity; ++i ) { | 36 | for ( size_t i = 0; i != d->map_capacity; ++i ) { |
| 37 | d->map[i] = NULL; | 37 | d->map[i] = NULL; |
| 38 | } | 38 | } |
| 39 | } | 39 | } |
| @@ -43,7 +43,7 @@ void | |||
| 43 | deque_free(struct deque *d) | 43 | deque_free(struct deque *d) |
| 44 | { | 44 | { |
| 45 | // free all chunks | 45 | // free all chunks |
| 46 | for ( size_t i = 0; i != d->capacity; ++i ) { | 46 | for ( size_t i = 0; i != d->map_capacity; ++i ) { |
| 47 | free(d->map[i]); | 47 | free(d->map[i]); |
| 48 | } | 48 | } |
| 49 | 49 | ||
| @@ -54,13 +54,13 @@ deque_free(struct deque *d) | |||
| 54 | static void | 54 | static void |
| 55 | grow_map(struct deque *d) | 55 | grow_map(struct deque *d) |
| 56 | { | 56 | { |
| 57 | const size_t capacity = d->capacity + d->capacity / 2; | 57 | const size_t capacity = d->map_capacity + d->map_capacity / 2; |
| 58 | T ** map = calloc(capacity, sizeof *map); | 58 | T ** map = calloc(map_capacity, sizeof *map); |
| 59 | 59 | ||
| 60 | // copy elements | 60 | // copy elements |
| 61 | size_t i; | 61 | size_t i; |
| 62 | for ( i = 0; i != d->capacity; ++i ) { | 62 | for ( i = 0; i != d->map_capacity; ++i ) { |
| 63 | map[i] = d->map[(i + d->first_chunk) % d->capacity]; | 63 | map[i] = d->map[(i + d->map_begin) % d->map_capacity]; |
| 64 | } | 64 | } |
| 65 | 65 | ||
| 66 | // initialize the rest (new) elements with NULL | 66 | // initialize the rest (new) elements with NULL |
| @@ -73,77 +73,77 @@ grow_map(struct deque *d) | |||
| 73 | d->map = map; | 73 | d->map = map; |
| 74 | 74 | ||
| 75 | // adjust pointers | 75 | // adjust pointers |
| 76 | d->first_chunk = 0; | 76 | d->map_begin = 0; |
| 77 | d->last_chunk = d->capacity - 1; | 77 | d->map_end = d->map_capacity - 1; |
| 78 | 78 | ||
| 79 | // set new capacity | 79 | // set new map_capacity |
| 80 | d->capacity = capacity; | 80 | d->map_capacity = capacity; |
| 81 | } | 81 | } |
| 82 | 82 | ||
| 83 | static void | 83 | static void |
| 84 | map_append_chunk(struct deque *d) | 84 | map_append_chunk(struct deque *d) |
| 85 | { | 85 | { |
| 86 | size_t next = (d->last_chunk + 1) % d->capacity; | 86 | size_t next = (d->map_end + 1) % d->map_capacity; |
| 87 | 87 | ||
| 88 | if ( next == d->first_chunk ) { // Resize the map | 88 | if ( next == d->map_begin ) { // Resize the map |
| 89 | grow_map(d); | 89 | grow_map(d); |
| 90 | 90 | ||
| 91 | next = d->last_chunk + 1; | 91 | next = d->map_end + 1; |
| 92 | } | 92 | } |
| 93 | 93 | ||
| 94 | d->map[d->last_chunk] = calloc(CHUNK_CAPACITY, sizeof **d->map); | 94 | d->map[d->map_end] = calloc(CHUNK_CAPACITY, sizeof **d->map); |
| 95 | d->last_chunk = next; | 95 | d->map_end = next; |
| 96 | } | 96 | } |
| 97 | 97 | ||
| 98 | static void | 98 | static void |
| 99 | map_prepend_chunk(struct deque *d) | 99 | map_prepend_chunk(struct deque *d) |
| 100 | { | 100 | { |
| 101 | size_t prev = (d->first_chunk + d->capacity - 1) % d->capacity; | 101 | size_t prev = (d->map_begin + d->map_capacity - 1) % d->map_capacity; |
| 102 | 102 | ||
| 103 | if ( prev == d->last_chunk ) { | 103 | if ( prev == d->map_end ) { |
| 104 | grow_map(d); | 104 | grow_map(d); |
| 105 | 105 | ||
| 106 | prev = d->capacity - 1; | 106 | prev = d->map_capacity - 1; |
| 107 | } | 107 | } |
| 108 | 108 | ||
| 109 | d->map[prev] = calloc(CHUNK_CAPACITY, sizeof **d->map); | 109 | d->map[prev] = calloc(CHUNK_CAPACITY, sizeof **d->map); |
| 110 | d->first_chunk = prev; | 110 | d->map_begin = prev; |
| 111 | } | 111 | } |
| 112 | 112 | ||
| 113 | static void | 113 | static void |
| 114 | map_remove_front_chunk(struct deque *d) | 114 | map_remove_front_chunk(struct deque *d) |
| 115 | { | 115 | { |
| 116 | if ( d->first_chunk == d->last_chunk ) | 116 | if ( d->map_begin == d->map_end ) |
| 117 | return; | 117 | return; |
| 118 | 118 | ||
| 119 | const size_t next = (d->first_chunk + 1) % d->capacity; | 119 | const size_t next = (d->map_begin + 1) % d->map_capacity; |
| 120 | 120 | ||
| 121 | free(d->map[d->first_chunk]); | 121 | free(d->map[d->map_begin]); |
| 122 | d->map[d->first_chunk] = NULL; | 122 | d->map[d->map_begin] = NULL; |
| 123 | 123 | ||
| 124 | d->first_chunk = next; | 124 | d->map_begin = next; |
| 125 | } | 125 | } |
| 126 | 126 | ||
| 127 | static void | 127 | static void |
| 128 | map_remove_tail_chunk(struct deque *d) | 128 | map_remove_tail_chunk(struct deque *d) |
| 129 | { | 129 | { |
| 130 | if ( d->first_chunk == d->last_chunk ) | 130 | if ( d->map_begin == d->map_end ) |
| 131 | return; | 131 | return; |
| 132 | 132 | ||
| 133 | const size_t prev = (d->last_chunk + d->capacity - 1) % d->capacity; | 133 | const size_t prev = (d->map_end + d->map_capacity - 1) % d->map_capacity; |
| 134 | 134 | ||
| 135 | free(d->map[prev]); | 135 | free(d->map[prev]); |
| 136 | d->map[prev] = NULL; | 136 | d->map[prev] = NULL; |
| 137 | 137 | ||
| 138 | d->last_chunk = prev; | 138 | d->map_end = prev; |
| 139 | } | 139 | } |
| 140 | 140 | ||
| 141 | void | 141 | void |
| 142 | deque_get_at(struct deque *d, size_t idx, T *data) | 142 | deque_get_at(struct deque *d, size_t idx, T *data) |
| 143 | { | 143 | { |
| 144 | const size_t offset = d->start + idx; | 144 | const size_t offset = d->offset + idx; |
| 145 | const size_t chunk_off = offset % CHUNK_CAPACITY; | 145 | const size_t chunk_off = offset % CHUNK_CAPACITY; |
| 146 | const size_t chunk_num = ((offset / CHUNK_CAPACITY) + d->first_chunk) % d->capacity; | 146 | const size_t chunk_num = ((offset / CHUNK_CAPACITY) + d->map_begin) % d->map_capacity; |
| 147 | 147 | ||
| 148 | *data = d->map[chunk_num][chunk_off]; | 148 | *data = d->map[chunk_num][chunk_off]; |
| 149 | } | 149 | } |
| @@ -151,13 +151,13 @@ deque_get_at(struct deque *d, size_t idx, T *data) | |||
| 151 | void | 151 | void |
| 152 | deque_push_back(struct deque *d, T data) | 152 | deque_push_back(struct deque *d, T data) |
| 153 | { | 153 | { |
| 154 | const size_t offset = d->start + d->size; | 154 | const size_t offset = d->offset + d->size; |
| 155 | const size_t chunk_off = offset % CHUNK_CAPACITY; | 155 | const size_t chunk_off = offset % CHUNK_CAPACITY; |
| 156 | size_t chunk_num = ((offset / CHUNK_CAPACITY) + d->first_chunk) % d->capacity; | 156 | size_t chunk_num = ((offset / CHUNK_CAPACITY) + d->map_begin) % d->map_capacity; |
| 157 | 157 | ||
| 158 | if ( chunk_num == d->last_chunk ) { | 158 | if ( chunk_num == d->map_end ) { |
| 159 | map_append_chunk(d); | 159 | map_append_chunk(d); |
| 160 | chunk_num = ((offset / CHUNK_CAPACITY) + d->first_chunk) % d->capacity; | 160 | chunk_num = ((offset / CHUNK_CAPACITY) + d->map_begin) % d->map_capacity; |
| 161 | } | 161 | } |
| 162 | 162 | ||
| 163 | d->map[chunk_num][chunk_off] = data; | 163 | d->map[chunk_num][chunk_off] = data; |
| @@ -170,17 +170,17 @@ deque_pop_front(struct deque *d, T *data) | |||
| 170 | if ( d->size == 0 ) | 170 | if ( d->size == 0 ) |
| 171 | return false; | 171 | return false; |
| 172 | 172 | ||
| 173 | const size_t chunk_off = d->start % CHUNK_CAPACITY; | 173 | const size_t chunk_off = d->offset % CHUNK_CAPACITY; |
| 174 | const size_t chunk_num = ((d->start / CHUNK_CAPACITY) + d->first_chunk) % d->capacity; | 174 | const size_t chunk_num = ((d->offset / CHUNK_CAPACITY) + d->map_begin) % d->map_capacity; |
| 175 | 175 | ||
| 176 | *data = d->map[chunk_num][chunk_off]; | 176 | *data = d->map[chunk_num][chunk_off]; |
| 177 | 177 | ||
| 178 | --d->size; | 178 | --d->size; |
| 179 | ++d->start; | 179 | ++d->offset; |
| 180 | 180 | ||
| 181 | if ( d->size == 0 || d->start == CHUNK_CAPACITY ) { | 181 | if ( d->size == 0 || d->offset == CHUNK_CAPACITY ) { |
| 182 | map_remove_front_chunk(d); | 182 | map_remove_front_chunk(d); |
| 183 | d->start = 0; | 183 | d->offset = 0; |
| 184 | } | 184 | } |
| 185 | 185 | ||
| 186 | return true; | 186 | return true; |
| @@ -189,9 +189,9 @@ deque_pop_front(struct deque *d, T *data) | |||
| 189 | static void | 189 | static void |
| 190 | deque_show(struct deque *d) | 190 | deque_show(struct deque *d) |
| 191 | { | 191 | { |
| 192 | printf("first: %zu -- last: %zu -- size: %zu -- capacity: %zu -- start: %zu\n", | 192 | printf("first: %zu -- last: %zu -- size: %zu -- map_capacity: %zu -- offset: %zu\n", |
| 193 | d->first_chunk, d->last_chunk, d->size, d->capacity, d->start); | 193 | d->map_begin, d->map_end, d->size, d->map_capacity, d->offset); |
| 194 | for ( size_t i = 0; i != d->capacity; ++i ) { | 194 | for ( size_t i = 0; i != d->map_capacity; ++i ) { |
| 195 | printf("%zu(%p) ", i, (void *) d->map[i]); | 195 | printf("%zu(%p) ", i, (void *) d->map[i]); |
| 196 | } | 196 | } |
| 197 | puts(""); | 197 | puts(""); |
