1 files changed, 23 insertions, 3 deletions

diff --git a/deque.c b/deque.c
index 5800997..36af05a 100644
--- a/deque.c
+++ b/deque.c
@@ -172,12 +172,33 @@ deque_push_front(struct deque *d, T data)
                 d->offset = CHUNK_CAPACITY;
         }
 
+        ++d->size;
         --d->offset;
 
         size_t chunk_num = (d->offset / CHUNK_CAPACITY + d->map_begin) % d->map_capacity;
 
         d->map[chunk_num][d->offset] = data;
-        ++d->size;
+}
+
+bool
+deque_pop_back(struct deque *d, T *data)
+{
+        if ( d->size == 0 )
+                return false;
+
+        --d->size;
+
+        const size_t offset    = d->offset + d->size;
+        const size_t chunk_off = offset % CHUNK_CAPACITY;
+        const size_t chunk_num = (offset / CHUNK_CAPACITY + d->map_begin) % d->map_capacity;
+
+        *data = d->map[chunk_num][chunk_off];
+
+        if ( d->size == 0 || chunk_off == 0 ) {
+                map_remove_tail_chunk(d);
+        }
+
+        return true;
 }
 
 bool
@@ -186,10 +207,9 @@ deque_pop_front(struct deque *d, T *data)
         if ( d->size == 0 )
                 return false;
 
-        const size_t chunk_off = d->offset % CHUNK_CAPACITY;
         const size_t chunk_num = (d->offset / CHUNK_CAPACITY + d->map_begin) % d->map_capacity;
 
-        *data = d->map[chunk_num][chunk_off];
+        *data = d->map[chunk_num][d->offset];
 
         --d->size;
         ++d->offset;