使用用户输入搜索数组并打印具有此值的所有元素

Question

I'm trying to search an array for a certain value and display all the elements which contain this value in java. For example, the user selects the number 5, there are 3 projects stored in the array with this value so all 3 of those will be printed out. My code is compiling ok, but when I run it, it jumps to the else statement, even if I am inputting a number that is in the array.. Any help would be amazing. Here's my code:

                case 3:
                //display all elements with the same state
                //get number user wishes to search for
                
                boolean found = false;
                 Scanner input = new Scanner(System.in);
                 System.out.print("Please enter the number you wish to search for");

                 //read user input
                 num = input.nextInt();

                 //traverse array
                 int k = 0;
                 for(k=0; k < myMonths.length; k++){
                     if(myMonths[index] == num){
                         found = true;
                         break;}
                     if(found){System.out.println(k);}

                     else{System.out.println("not found");}
                 }
                break;

Here's the array:

            //Menu loop
            int myMonths[] = new int[5];
            int index = 0;
            int num;
            while(choice !=6){


                switch (choice){
                case 1:
                //int n = number of projects
                int n = 1;
                Scanner sc = new Scanner(System.in);
                System.out.println("How many months was your project?");


                for(int i=0; i<1; i++){
                    int a = sc.nextInt();

                    //if months is lesser than 2/greater than 12
                    if((a < 2) || (a > 12)){
                        System.out.println("Please enter an amount between 2 and 12 months");}

                   //if months is between 2 and 12 add it to the array

                    else{myMonths[index++] = a;} }
                break;

Answer 1

First, you should be using k instead of index . Second, you shouldn't be printing "not found" (or testing for that) on every iteration. You should limit variable scope as much as practical. And you also mention wanting to find all matching indices so you shouldn't terminate the loop prematurely; I think you wanted something like

//assume the value isn't present.
boolean found = false;
//read user input
int num = input.nextInt();

//traverse array
for(int k = 0; k < myMonths.length; k++) {
    if (myMonths[k] == num){
        found = true;
        System.out.println(k); // don't break or the loop ends early.
    }
}
//this test can only be done after you iterate **all** values.
if (!found) {
    System.out.println("not found");
}