Write a function that takes a string of characters and an integer n and returns the most frequent n-gram.
Example: for ‘abcdabxexexe’ and 2 returns ‘xe’.
This is the solution I came up with but feel like there's a more efficient way of doing it rather than calling substring each time which takes O(n). Any thoughts?
public String mostCommonNGram(String word, int n) {
Map<String, Integer> nGramCount = new HashMap<>();
for (int i = 0; i <= word.length() - n; i++) {
String currGram = word.substring(i, i+n); // Potentially more efficient way?
nGramCount.put(currGram, nGramCount.getOrDefault(currGram, 0) + 1);
}
int max = 0;
String ans = "";
for (Map.Entry<String, Integer> entry : nGramCount.entrySet()) {
if (entry.getValue() > max) {
max = entry.getValue();
ans = entry.getKey();
}
}
return ans;
}Comments (4)