bucket_sort_.java

public class bucket_sort_ {
	class Solution {
	    public String frequencySort(String s) {
	       char[] str=s.toCharArray();
	        int[] freq=new int[128];
	        // for(char ch:s) freq[ch]++;
	        for(int i=0;i<str.length;i++) freq[str[i]]++;
	        for(int i=0;i<str.length;){
	            char cmax=',';
	            for(int j=0;j<128;j++){
	                if(freq[j]>freq[cmax]) cmax=(char)j;
	            }
	            while(freq[cmax]!=0){
	                str[i++]=cmax;
	                freq[cmax]--;
	            }
	        }
	        return new String(str);
	    }
	}
}