diff --git a/native/src/proximity_info.cpp b/native/src/proximity_info.cpp
index 209c31e..ebf83a7 100644
--- a/native/src/proximity_info.cpp
+++ b/native/src/proximity_info.cpp
@@ -63,4 +63,29 @@
     return false;
 }
 
+// TODO: Calculate nearby codes here.
+void ProximityInfo::setInputParams(const int* inputCodes, const int inputLength) {
+    mInputCodes = inputCodes;
+    mInputLength = inputLength;
+}
+
+const int* ProximityInfo::getProximityCharsAt(const int index) const {
+    return mInputCodes + (index * MAX_PROXIMITY_CHARS_SIZE);
+}
+
+bool ProximityInfo::sameAsTyped(const unsigned short *word, int length) const {
+    if (length != mInputLength) {
+        return false;
+    }
+    const int *inputCodes = mInputCodes;
+    while (length--) {
+        if ((unsigned int) *inputCodes != (unsigned int) *word) {
+            return false;
+        }
+        inputCodes += MAX_PROXIMITY_CHARS_SIZE;
+        word++;
+    }
+    return true;
+}
+
 } // namespace latinime
diff --git a/native/src/proximity_info.h b/native/src/proximity_info.h
index 327cd09..0d7c9c5 100644
--- a/native/src/proximity_info.h
+++ b/native/src/proximity_info.h
@@ -30,6 +30,9 @@
             const uint32_t *proximityCharsArray);
     ~ProximityInfo();
     bool hasSpaceProximity(const int x, const int y) const;
+    void setInputParams(const int* inputCodes, const int inputLength);
+    const int* getProximityCharsAt(const int index) const;
+    bool sameAsTyped(const unsigned short *word, int length) const;
 private:
     int getStartIndexFromCoordinates(const int x, const int y) const;
     const int MAX_PROXIMITY_CHARS_SIZE;
@@ -39,7 +42,9 @@
     const int GRID_HEIGHT;
     const int CELL_WIDTH;
     const int CELL_HEIGHT;
+    const int *mInputCodes;
     uint32_t *mProximityCharsArray;
+    int mInputLength;
 };
 
 } // namespace latinime
diff --git a/native/src/unigram_dictionary.cpp b/native/src/unigram_dictionary.cpp
index 698584e..5873e21 100644
--- a/native/src/unigram_dictionary.cpp
+++ b/native/src/unigram_dictionary.cpp
@@ -54,7 +54,7 @@
       // TODO : remove this variable.
     ROOT_POS(0),
 #endif // NEW_DICTIONARY_FORMAT
-    BYTES_IN_ONE_CHAR(MAX_PROXIMITY_CHARS * sizeof(*mInputCodes)),
+    BYTES_IN_ONE_CHAR(MAX_PROXIMITY_CHARS * sizeof(int)),
     MAX_UMLAUT_SEARCH_DEPTH(DEFAULT_MAX_UMLAUT_SEARCH_DEPTH) {
     if (DEBUG_DICT) {
         LOGI("UnigramDictionary - constructor");
@@ -93,7 +93,7 @@
 // codesDest is the current point in the work buffer.
 // codesSrc is the current point in the user-input, original, content-unmodified buffer.
 // codesRemain is the remaining size in codesSrc.
-void UnigramDictionary::getWordWithDigraphSuggestionsRec(const ProximityInfo *proximityInfo,
+void UnigramDictionary::getWordWithDigraphSuggestionsRec(ProximityInfo *proximityInfo,
         const int *xcoordinates, const int* ycoordinates, const int *codesBuffer,
         const int codesBufferSize, const int flags, const int* codesSrc, const int codesRemain,
         const int currentDepth, int* codesDest, unsigned short* outWords, int* frequencies) {
@@ -143,7 +143,7 @@
             (codesDest - codesBuffer) / MAX_PROXIMITY_CHARS + codesRemain, outWords, frequencies);
 }
 
-int UnigramDictionary::getSuggestions(const ProximityInfo *proximityInfo, const int *xcoordinates,
+int UnigramDictionary::getSuggestions(ProximityInfo *proximityInfo, const int *xcoordinates,
         const int *ycoordinates, const int *codes, const int codesSize, const int flags,
         unsigned short *outWords, int *frequencies) {
 
@@ -187,13 +187,14 @@
     return suggestedWordsCount;
 }
 
-void UnigramDictionary::getWordSuggestions(const ProximityInfo *proximityInfo,
+void UnigramDictionary::getWordSuggestions(ProximityInfo *proximityInfo,
         const int *xcoordinates, const int *ycoordinates, const int *codes, const int codesSize,
         unsigned short *outWords, int *frequencies) {
 
     PROF_OPEN;
     PROF_START(0);
-    initSuggestions(codes, codesSize, outWords, frequencies);
+    initSuggestions(
+            proximityInfo, xcoordinates, ycoordinates, codes, codesSize, outWords, frequencies);
     if (DEBUG_DICT) assert(codesSize == mInputLength);
 
     const int MAX_DEPTH = min(mInputLength * MAX_DEPTH_MULTIPLIER, MAX_WORD_LENGTH);
@@ -275,16 +276,18 @@
     PROF_END(6);
 }
 
-void UnigramDictionary::initSuggestions(const int *codes, const int codesSize,
+void UnigramDictionary::initSuggestions(ProximityInfo *proximityInfo, const int *xcoordinates,
+        const int *ycoordinates, const int *codes, const int codesSize,
         unsigned short *outWords, int *frequencies) {
     if (DEBUG_DICT) {
         LOGI("initSuggest");
     }
     mFrequencies = frequencies;
     mOutputChars = outWords;
-    mInputCodes = codes;
     mInputLength = codesSize;
     mMaxEditDistance = mInputLength < 5 ? 2 : mInputLength / 2;
+    proximityInfo->setInputParams(codes, codesSize);
+    mProximityInfo = proximityInfo;
 }
 
 static inline void registerNextLetter(unsigned short c, int *nextLetters, int nextLettersSize) {
@@ -360,21 +363,6 @@
     return c;
 }
 
-bool UnigramDictionary::sameAsTyped(const unsigned short *word, int length) const {
-    if (length != mInputLength) {
-        return false;
-    }
-    const int *inputCodes = mInputCodes;
-    while (length--) {
-        if ((unsigned int) *inputCodes != (unsigned int) *word) {
-            return false;
-        }
-        inputCodes += MAX_PROXIMITY_CHARS;
-        word++;
-    }
-    return true;
-}
-
 static const char QUOTE = '\'';
 static const char SPACE = ' ';
 
@@ -569,6 +557,8 @@
     if (excessivePos >= 0) {
         multiplyRate(WORDS_WITH_EXCESSIVE_CHARACTER_DEMOTION_RATE, &finalFreq);
         if (!existsAdjacentProximityChars(inputIndex, mInputLength)) {
+            // If an excessive character is not adjacent to the left char or the right char,
+            // we will demote this word.
             multiplyRate(WORDS_WITH_EXCESSIVE_CHARACTER_OUT_OF_PROXIMITY_DEMOTION_RATE, &finalFreq);
         }
     }
@@ -678,7 +668,7 @@
         const int excessivePos, const int transposedPos, const int freq, const bool sameLength,
         int* nextLetters, const int nextLettersSize) {
 
-    const bool isSameAsTyped = sameLength ? sameAsTyped(word, depth + 1) : false;
+    const bool isSameAsTyped = sameLength ? mProximityInfo->sameAsTyped(word, depth + 1) : false;
     if (isSameAsTyped) return;
 
     if (depth >= MIN_SUGGEST_DEPTH) {
diff --git a/native/src/unigram_dictionary.h b/native/src/unigram_dictionary.h
index dcc8f2a..70702a9 100644
--- a/native/src/unigram_dictionary.h
+++ b/native/src/unigram_dictionary.h
@@ -82,26 +82,26 @@
             int maxAlternatives);
 #endif // NEW_DICTIONARY_FORMAT
     int getBigramPosition(int pos, unsigned short *word, int offset, int length) const;
-    int getSuggestions(const ProximityInfo *proximityInfo, const int *xcoordinates,
+    int getSuggestions(ProximityInfo *proximityInfo, const int *xcoordinates,
             const int *ycoordinates, const int *codes, const int codesSize, const int flags,
             unsigned short *outWords, int *frequencies);
     ~UnigramDictionary();
 
 private:
-    void getWordSuggestions(const ProximityInfo *proximityInfo, const int *xcoordinates,
+    void getWordSuggestions(ProximityInfo *proximityInfo, const int *xcoordinates,
             const int *ycoordinates, const int *codes, const int codesSize,
             unsigned short *outWords, int *frequencies);
     bool isDigraph(const int* codes, const int i, const int codesSize) const;
-    void getWordWithDigraphSuggestionsRec(const ProximityInfo *proximityInfo,
+    void getWordWithDigraphSuggestionsRec(ProximityInfo *proximityInfo,
         const int *xcoordinates, const int* ycoordinates, const int *codesBuffer,
         const int codesBufferSize, const int flags, const int* codesSrc, const int codesRemain,
         const int currentDepth, int* codesDest, unsigned short* outWords, int* frequencies);
-    void initSuggestions(const int *codes, const int codesSize, unsigned short *outWords,
-            int *frequencies);
+    void initSuggestions(ProximityInfo *proximityInfo, const int *xcoordinates,
+            const int *ycoordinates, const int *codes, const int codesSize,
+            unsigned short *outWords, int *frequencies);
     void getSuggestionCandidates(const int skipPos, const int excessivePos,
             const int transposedPos, int *nextLetters, const int nextLettersSize,
             const int maxDepth);
-    bool sameAsTyped(const unsigned short *word, int length) const;
     bool addWord(unsigned short *word, int length, int frequency);
     bool getSplitTwoWordsSuggestion(const int inputLength,
             const int firstWordStartPos, const int firstWordLength,
@@ -129,7 +129,7 @@
             int *newDiffs, int *nextSiblingPosition, int *nextOutputIndex);
     bool existsAdjacentProximityChars(const int inputIndex, const int inputLength) const;
     inline const int* getInputCharsAt(const int index) const {
-        return mInputCodes + (index * MAX_PROXIMITY_CHARS);
+        return mProximityInfo->getProximityCharsAt(index);
     }
     int getMostFrequentWordLike(const int startInputIndex, const int inputLength,
             unsigned short *word);
@@ -174,7 +174,7 @@
 
     int *mFrequencies;
     unsigned short *mOutputChars;
-    const int *mInputCodes;
+    const ProximityInfo *mProximityInfo;
     int mInputLength;
     // MAX_WORD_LENGTH_INTERNAL must be bigger than MAX_WORD_LENGTH
     unsigned short mWord[MAX_WORD_LENGTH_INTERNAL];