How can I check number present or not in Java

Question

I have to display that given number present in array or not. For example:

int[] number1 = {2,3,6,14,23,8,23,19};   
int[] numbers2 = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30};

Now I have to check whether number1 array element present in number2 array or not if yes then print present number. So how can I achieve this in Java?

My code:

int[] number1 = {2,3,6,14,23,8,23,19};   
    int[] numbers2 = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30};

for(int i=0; i<number2.length;i++){
    for(int j =0; j<number1.length:j++){
        if(number2[i]==number1[j]){
            System.out.println("present number is:"+number1[i]);
        }
    }
}

Yes, I will try, but when I execute the program, it will check only the first value of number1 array. — Gaurav Takte, Apr 19 '17 at 12:31
Change i --> j at System.out.println("present number is:"+number1[j]); — gifpif, Apr 19 '17 at 12:49
Possible duplicate of [How can I test if an array contains a certain value?](http://stackoverflow.com/questions/1128723/how-can-i-test-if-an-array-contains-a-certain-value) — pringi, Apr 19 '17 at 13:36

score 3 · Accepted Answer · answered Apr 19 '17 at 12:34

A nested for loop will help you to achieve that, basically for each number in number1, you need to traverse numbers2 to see if the value is present.

for(int i: number1) {
        for(int j: numbers2) {
            if(i == j) {
                System.out.println(i);
                break; //exit the inner loop if the number is present
            }
        }
    }

score 1 · Answer 2 · answered Apr 19 '17 at 12:34

1

This is the basic idea

Iterate through the first array using a for loop.
Use an inner for loop to iterate through the elements of second array and keep comparing the value.
If the value is found, print it and break out of inner loop.

answered Apr 19 '17 at 12:34

Pooja Arora

574
7
19

score 1 · Answer 3 · answered Apr 19 '17 at 12:53

1

Change i --> j at System.out.println("present number is:"+number1[j]);

answered Apr 19 '17 at 12:53

gifpif

4,507
4
31
45

score 0 · Answer 4 · answered Apr 19 '17 at 12:35

It's simple and clean when using Java 8.

int[] number1 = {2,3,6,14,23,8,55,23,19};
int[] numbers2 = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30};

Arrays.stream(numbers2)
        .filter(num -> Arrays.stream(number1).anyMatch(e -> e == num))
        .forEach(System.out::println);

How can I check number present or not in Java

4 Answers4