Question

import ...

@Component({ ... })

export class TestComponent implements OnInit {
// A Couple of @Input statements
@Input() ...

// Create Formcontrollers
 controlNumber = new FormControl("", [Validators.pattern("[0-9]*")]);
 controlText = new FormControl("", [Validators.pattern("[A-Z-a-z]*")]);
 datePicker = new FormControl(moment());


 constructor(private http: HttpClient) {  }

 ngOnInit() {
 }

 ...

 getNotANumberMessage() {
  return this.controlNumber .hasError("pattern") ? "Numbers only" : "";
 }

 getNotAStringMessage() {
   return this.controlText.hasError("pattern") ? "Strings only" : "";
 }
 }

这是我目前得到的：

int curr = 0;
int cnt;
String element = values[0][0];
int numberRepeats = 0;//cnt-counter,what's the element ,how many times it's repeated

     for (int i = 0; i < values.length; i++) {
        for (int j = 0; j < values[i].length; j++) {//those two for's are for the current element
            cnt = 0;//counter is nullified
            for (int j2 = i; j2 < values.length; j2++) {
                for (int k = 0; k < values[j2].length; k++) {//and those two are the compared element
                    if (values[i][j] == values[j2][k]) {//if the current element is the same as the compared element,increase counter
                        cnt++;                        
                    }
                }

            if (cnt >numberRepeats) {//after the compared element is done comparing and the number of repeats of the current element is more then the lastly checked element
                element = values[i][j];//we get the element ,and how many times it's repeated
                numberRepeats = cnt;
            }
        }
    }
}    
System.out.println();
System.out.println("The most popular item is: "+element+". Number sold:"+numberRepeats);`

这就是我想要得到的：

houseShampoo    meatPork    dairyCream  wheatBread  wheatCrackers   
houseShampoo    houseShampoo    houseDetergent  meatPork    dairyYogurt 
meatLamb    dairyMilk   dairyCream  meatPork    houseShampoo    
wheatCookies    meatLamb    dairyYogurt wheatCereal wheatBread  
meatLamb    dairyMilk   wheatCookies    wheatCrackers   wheatPasta  

The most popular item is: houseShampoo. Number sold:4

但是我不知道如何更改The least popular item is: wheatPasta. Number sold:1语句中的条件以给出最不频繁的元素，而不是最流行的元素

Answer 1

由于您希望找到最少的重复次数，因此请从最大值的初始值开始：

int numberRepeats = Integer.MAX_VALUE;

，当发现重复次数较少的项目时，将其替换：

if (cnt < numberRepeats) {
    element = values[i][j];
    numberRepeats = cnt;
}

这应该可以解决问题。

Answer 2

嗨，我选择了使用Map的其他方法，希望对您有所帮助:)

int dimension = 3;
    int sold = 0;
    String product = "";
    Map<String,Integer> productsSoldAndCount = new HashMap<>();
    String[][] elements = new String[3][3];
    elements[0] = new String[]{"houseShampoo","meatpork","dairyCream"};
    elements[1] = new String[]{"houseShampoo","bread","cookies"};
    elements[2] = new String[]{"meatpork","meatpork","meatpork"};

    for(var tmpArray : elements){
        for(var tmpString : tmpArray){
            if(!productsSoldAndCount.containsKey(tmpString)){
                productsSoldAndCount.put(tmpString,1);
            }else{
                productsSoldAndCount.put(tmpString,productsSoldAndCount.get(tmpString) + 1);
            }
        }
    }

    for(var resultPair : productsSoldAndCount.entrySet()){
        if(resultPair.getValue() > sold){
            sold = resultPair.getValue();
            product = resultPair.getKey();
        }
    }
    System.out.println("The most popular item is: " + product + " Sold: " + sold);

需要获取2D数组的最少频率元素

2 个答案: