FB面经 Prepare: Task Schedule

tasks has cooldown time, give an input task id array, output finish time
input: AABCA
A--ABCA
output:7

 

package fb;

import java.util.*;

public class Scheduler {
    
    public int task(int[] tasks, int cooldown) {
        int time = 0;
        HashMap<Integer, Integer> map = new HashMap<Integer, Integer>();
        
        StringBuilder output = new StringBuilder();
        
        for (int i=0; i<tasks.length; i++) {
            if (!map.containsKey(tasks[i]) || time>=map.get(tasks[i])) {
                map.put(tasks[i], time+cooldown);
                time++;
                
                output.append(tasks[i]);
            }
            else { // time < map.get(tasks[i])
                for (int k=time; k<map.get(tasks[i]); k++) {
                    output.append("-");
                }
                
                
                time = map.get(tasks[i]);
                map.put(tasks[i], time+cooldown);
                time++;
                
                
                output.append(tasks[i]);
            }
        }
        return time;
    }
    
    public static void main(String[] args) {
        Scheduler sc = new Scheduler();
        //int res = sc.task(new int[]{1,1,2,3,1}, 3);
        int res = sc.task(new int[]{1,2,1,2,3}, 3);
        //String output = sc.task(new int[]{1,2,2,1,3}, 3);
        System.out.println(res);
        //System.out.println(output);
    }
}