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diff --git a/native/jni/src/multi_bigram_map.h b/native/jni/src/multi_bigram_map.h
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+++ b/native/jni/src/multi_bigram_map.h
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+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef LATINIME_MULTI_BIGRAM_MAP_H
+#define LATINIME_MULTI_BIGRAM_MAP_H
+
+#include <cstring>
+#include <stdint.h>
+
+#include "defines.h"
+#include "binary_format.h"
+#include "hash_map_compat.h"
+
+namespace latinime {
+
+// Class for caching bigram maps for multiple previous word contexts. This is useful since the
+// algorithm needs to look up the set of bigrams for every word pair that occurs in every
+// multi-word suggestion.
+class MultiBigramMap {
+ public:
+    MultiBigramMap() : mBigramMaps() {}
+    ~MultiBigramMap() {}
+
+    // Look up the bigram probability for the given word pair from the cached bigram maps.
+    // Also caches the bigrams if there is space remaining and they have not been cached already.
+    int getBigramProbability(const uint8_t *const dicRoot, const int wordPosition,
+            const int nextWordPosition, const int unigramProbability) {
+        hash_map_compat<int, BigramMap>::const_iterator mapPosition =
+                mBigramMaps.find(wordPosition);
+        if (mapPosition != mBigramMaps.end()) {
+            return mapPosition->second.getBigramProbability(nextWordPosition, unigramProbability);
+        }
+        if (mBigramMaps.size() < MAX_CACHED_PREV_WORDS_IN_BIGRAM_MAP) {
+            addBigramsForWordPosition(dicRoot, wordPosition);
+            return mBigramMaps[wordPosition].getBigramProbability(
+                    nextWordPosition, unigramProbability);
+        }
+        return BinaryFormat::getBigramProbability(
+                dicRoot, wordPosition, nextWordPosition, unigramProbability);
+    }
+
+    void clear() {
+        mBigramMaps.clear();
+    }
+
+ private:
+    DISALLOW_COPY_AND_ASSIGN(MultiBigramMap);
+
+    class BigramMap {
+     public:
+        BigramMap() : mBigramMap(DEFAULT_HASH_MAP_SIZE_FOR_EACH_BIGRAM_MAP) {}
+        ~BigramMap() {}
+
+        void init(const uint8_t *const dicRoot, int position) {
+            BinaryFormat::fillBigramProbabilityToHashMap(dicRoot, position, &mBigramMap);
+        }
+
+        inline int getBigramProbability(const int nextWordPosition, const int unigramProbability)
+                const {
+           return BinaryFormat::getBigramProbabilityFromHashMap(
+                   nextWordPosition, &mBigramMap, unigramProbability);
+        }
+
+     private:
+        // Note: Default copy constructor needed for use in hash_map.
+        hash_map_compat<int, int> mBigramMap;
+    };
+
+    void addBigramsForWordPosition(const uint8_t *const dicRoot, const int position) {
+        mBigramMaps[position].init(dicRoot, position);
+    }
+
+    hash_map_compat<int, BigramMap> mBigramMaps;
+};
+} // namespace latinime
+#endif // LATINIME_MULTI_BIGRAM_MAP_H