diff --git a/native/src/defines.h b/native/src/defines.h
index c1eaf0d..7fa7e35 100644
--- a/native/src/defines.h
+++ b/native/src/defines.h
@@ -151,6 +151,9 @@
 #define MIN_USER_TYPED_LENGTH_FOR_MISSING_SPACE_SUGGESTION 3
 #define MIN_USER_TYPED_LENGTH_FOR_EXCESSIVE_CHARACTER_SUGGESTION 3
 
+// The size of next letters frequency array.  Zero will disable the feature.
+#define NEXT_LETTERS_SIZE 0
+
 #define min(a,b) ((a)<(b)?(a):(b))
 
 #endif // LATINIME_DEFINES_H
diff --git a/native/src/dictionary.h b/native/src/dictionary.h
index cef1cf9..941bd19 100644
--- a/native/src/dictionary.h
+++ b/native/src/dictionary.h
@@ -27,10 +27,8 @@
 public:
     Dictionary(void *dict, int dictSize, int mmapFd, int dictBufAdjust, int typedLetterMultipler,
             int fullWordMultiplier, int maxWordLength, int maxWords, int maxAlternatives);
-    int getSuggestions(int *codes, int codesSize, unsigned short *outWords, int *frequencies,
-            int *nextLetters, int nextLettersSize) {
-        return mUnigramDictionary->getSuggestions(codes, codesSize, outWords, frequencies,
-                nextLetters, nextLettersSize);
+    int getSuggestions(int *codes, int codesSize, unsigned short *outWords, int *frequencies) {
+        return mUnigramDictionary->getSuggestions(codes, codesSize, outWords, frequencies);
     }
 
     // TODO: Call mBigramDictionary instead of mUnigramDictionary
diff --git a/native/src/unigram_dictionary.cpp b/native/src/unigram_dictionary.cpp
index dfbe822..3d5683e 100644
--- a/native/src/unigram_dictionary.cpp
+++ b/native/src/unigram_dictionary.cpp
@@ -32,7 +32,7 @@
 UnigramDictionary::UnigramDictionary(const unsigned char *dict, int typedLetterMultiplier,
         int fullWordMultiplier, int maxWordLength, int maxWords, int maxProximityChars,
         const bool isLatestDictVersion)
-    : DICT(dict), MAX_WORD_LENGTH(maxWordLength),MAX_WORDS(maxWords),
+    : DICT(dict), MAX_WORD_LENGTH(maxWordLength), MAX_WORDS(maxWords),
     MAX_PROXIMITY_CHARS(maxProximityChars), IS_LATEST_DICT_VERSION(isLatestDictVersion),
     TYPED_LETTER_MULTIPLIER(typedLetterMultiplier), FULL_WORD_MULTIPLIER(fullWordMultiplier),
     ROOT_POS(isLatestDictVersion ? DICTIONARY_HEADER_SIZE : 0) {
@@ -42,7 +42,7 @@
 UnigramDictionary::~UnigramDictionary() {}
 
 int UnigramDictionary::getSuggestions(int *codes, int codesSize, unsigned short *outWords,
-        int *frequencies, int *nextLetters, int nextLettersSize) {
+        int *frequencies) {
     PROF_OPEN;
     PROF_START(0);
     initSuggestions(codes, codesSize, outWords, frequencies);
@@ -52,7 +52,7 @@
     PROF_END(0);
 
     PROF_START(1);
-    getSuggestionCandidates(-1, -1, -1, nextLetters, nextLettersSize, MAX_DEPTH);
+    getSuggestionCandidates(-1, -1, -1, mNextLettersFrequency, NEXT_LETTERS_SIZE, MAX_DEPTH);
     PROF_END(1);
 
     PROF_START(2);
@@ -108,9 +108,9 @@
     if (DEBUG_DICT) {
         LOGI("Returning %d words", suggestedWordsCount);
         LOGI("Next letters: ");
-        for (int k = 0; k < nextLettersSize; k++) {
-            if (nextLetters[k] > 0) {
-                LOGI("%c = %d,", k, nextLetters[k]);
+        for (int k = 0; k < NEXT_LETTERS_SIZE; k++) {
+            if (mNextLettersFrequency[k] > 0) {
+                LOGI("%c = %d,", k, mNextLettersFrequency[k]);
             }
         }
     }
diff --git a/native/src/unigram_dictionary.h b/native/src/unigram_dictionary.h
index 90c9814..43aafc6 100644
--- a/native/src/unigram_dictionary.h
+++ b/native/src/unigram_dictionary.h
@@ -32,8 +32,7 @@
 public:
     UnigramDictionary(const unsigned char *dict, int typedLetterMultipler, int fullWordMultiplier,
             int maxWordLength, int maxWords, int maxProximityChars, const bool isLatestDictVersion);
-    int getSuggestions(int *codes, int codesSize, unsigned short *outWords, int *frequencies,
-            int *nextLetters, int nextLettersSize);
+    int getSuggestions(int *codes, int codesSize, unsigned short *outWords, int *frequencies);
     ~UnigramDictionary();
 
 private:
@@ -109,6 +108,7 @@
     int mStackInputIndex[MAX_WORD_LENGTH_INTERNAL];
     int mStackDiffs[MAX_WORD_LENGTH_INTERNAL];
     int mStackSiblingPos[MAX_WORD_LENGTH_INTERNAL];
+    int mNextLettersFrequency[NEXT_LETTERS_SIZE];
 };
 
 // ----------------------------------------------------------------------------