Daily practice ----- realize the lottery function of two-color ball. Rules: Six non repeating numbers are randomly selected from 36 red balls, and one from 15 basketball is randomly selected to form a

subject : Realize the lottery function of two-color ball . The rules ： from 36 Randomly choose the non repeating one among the red balls 6 Number , from 15 Randomly choose from basketball 1 Make up a lottery . You can choose to buy more notes .

The key to solving the problem is : Generation of random number range ; Red balls are random numbers that do not repeat ; You can buy more lottery tickets

Ideas :1) Write the number of tickets you need to buy

        2) Set the array of red balls , The array length is 6

        3) Numbers that randomly generate red balls ( Use the cycle )

        4) Judge whether the randomly generated number duplicates the previous number

       5) If there is a repetition with the previous element, it is flase

        6) Output flag by true Red Globe number of

        7) Set the array of basketball

The process :  Next, we write code step by step according to our problem-solving ideas

        1) Write the number of tickets you need to buy

        System.out.println(" Please enter the number of lottery tickets you need to buy :");
        Scanner sc = new Scanner(System.in);
        int num = sc.nextInt();
        System.out.println(" Did you buy it " + num + " Note lottery ");

        2) Set the array of red balls , The array length is 6

        int[] redNum = new int[6];

        3) Numbers that randomly generate red balls ( Use the cycle )
        for (int i = 1; i <= num; i++) {
            for (int j = 0; j < redNum.length; j++) {
                boolean flag = true;// Suppose there are no elements at this time ture
                int redNum1 = (int) (Math.random() * 36 + 1);    
                redNum[j] = redNum1;         

4) Judge whether the randomly generated number duplicates the previous number
                for (int k = 0; k < j; k++) {
                    if(redNum1 == redNum[k]){

5) If there is a repetition with the previous element, it is flase
                        flag = false;
                        j -=1;//j Self reduction 1, In this case, the repeated number will be output again
                        break;
                    }

       }

 6) Output flag by true Red Globe number of
                if(flag){
                System.out.print(redNum[j] + " ");
                }

7) Set the array of basketball
            int blueNum = (int) (Math.random() * 15 + 1);
            System.out.print(blueNum);
            System.out.println();

   The complete results are as follows :

  summary :

         The knowledge points used in this topic are the generation of random numbers , The assignment of an array , And the mark , The more important one is the mark

        Mark ( The red part of the code ): Assume that the variables are true, When a certain condition is met , This variable is changed to false, Last use if Judge that the output meets the condition of true or flase Variable value .

For the convenience of everyone , The source code is attached below :

//1) Write the number of tickets you need to buy 
		System.out.println(" Please enter the number of lottery tickets you need to buy :");
		Scanner sc = new Scanner(System.in);
		int num = sc.nextInt();
		System.out.println(" Did you buy it " + num + " Note lottery ");
		//2) Set the array of red balls , The array length is 6
		int[] redNum = new int[6];
		//3) Numbers that randomly generate red balls ( Use the cycle )
		for (int i = 1; i <= num; i++) {
			for (int j = 0; j < redNum.length; j++) {
				boolean flag = true;// Suppose there are no elements at this time ture
				int redNum1 = (int) (Math.random() * 36 + 1);	
				redNum[j] = redNum1;
				//4) Judge whether the randomly generated number duplicates the previous number 
				for (int k = 0; k < j; k++) {
					if(redNum1 == redNum[k]){
						//5) If there is a repetition with the previous element, it is flase
						flag = false;
						j -=1;//j Self reduction 1, In this case, the repeated number will be output again 
						break;
					}
				}
				//6) Output flag by true Red Globe number of 
				if(flag){
				System.out.print(redNum[j] + " ");
				}
			}
			//7) Set the array of basketball 
			int blueNum = (int) (Math.random() * 15 + 1);
			System.out.print(blueNum);
			System.out.println();
		}

Practice tomorrow :  Output the contents of the following pictures

You can write by yourself , Tomorrow, 12 I'll send my writing on time , Tomorrow, 12 I'll see you when I see you