Count occurance of string in an array

0 votes

Please help me find a way to solve this efficiently.

Problem statement: Find individual occurance of every character in an array.

Input:

[a,a,a,b,b,b,c,c,c,c,a]

Output:

a: 4
b: 3
c: 4
Mar 6, 2019 in Java by Bobin
55 views

1 answer to this question.

0 votes

You can use hashmap to solve this, here is the function for implementing it,

Map<String,Integer> hm = new HashMap();
for(String x:array){
    if(!hm.containsKey(x)){
        hm.put(x,1);
    }else{
        hm.put(x, hm.get(x)+1);
    }
}
System.out.println(hm);
answered Mar 7, 2019 by Priyaj
• 57,530 points

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