I am writing a very basic java program that calculates frequency of each word in a sentence so far i managed to do this much
import java.io.*;
class Linked {
public static void main(String args[]) throws IOException {
BufferedReader br = new BufferedReader(
new InputStreamReader(System.in));
System.out.println("Enter the sentence");
String st = br.readLine();
st = st + " ";
int a = lengthx(st);
String arr[] = new String[a];
int p = 0;
int c = 0;
for (int j = 0; j < st.length(); j++) {
if (st.charAt(j) == ' ') {
arr[p++] = st.substring(c,j);
c = j + 1;
}
}
}
static int lengthx(String a) {
int p = 0;
for (int j = 0; j < a.length(); j++) {
if (a.charAt(j) == ' ') {
p++;
}
}
return p;
}
}
I have extracted each string and stored it in a array , now problem is actually how to count the no of instances where each 'word' is repeated and how to display so that repeated words not get displayed multiple times , can you help me in this one ?
Use a map with word as a key and count as value, somthing like this
Map<String, Integer> map = new HashMap<>();
for (String w : words) {
Integer n = map.get(w);
n = (n == null) ? 1 : ++n;
map.put(w, n);
}
if you are not allowed to use java.util then you can sort arr using some sorting algoritm and do this
String[] words = new String[arr.length];
int[] counts = new int[arr.length];
words[0] = words[0];
counts[0] = 1;
for (int i = 1, j = 0; i < arr.length; i++) {
if (words[j].equals(arr[i])) {
counts[j]++;
} else {
j++;
words[j] = arr[i];
counts[j] = 1;
}
}
An interesting solution with ConcurrentHashMap since Java 8
ConcurrentMap<String, Integer> m = new ConcurrentHashMap<>();
m.compute("x", (k, v) -> v == null ? 1 : v + 1);