--- /dev/null
+
+#ifndef FASTQ_TOOLS_HASH_H
+#define FASTQ_TOOLS_HASH_H
+
+#include <stdlib.h>
+#include <stdint.h>
+
+
+typedef struct hashed_value_
+{
+ char* value;
+ size_t len;
+ uint32_t count;
+ struct hashed_value_* next;
+} hashed_value;
+
+
+typedef struct
+{
+ hashed_value** A; /* table proper */
+ size_t n; /* table size */
+ size_t m; /* hashed items */
+ size_t max_m; /* max hashed items before rehash */
+} hash_table;
+
+
+hash_table* create_hash_table();
+
+void destroy_hash_table(hash_table*);
+
+void inc_hash_table(hash_table*, const char* value, size_t len);
+
+hashed_value** dump_hash_table(hash_table*);
+
+
+#endif
+