Write a Java program, generate a random number from 0 to 9 at the beginning, and win the prize when the difference between the 100 and 10 of the user's membership number is equal to this random number.
Public static void main(String[] args) {
Random Random = new Random()； //Random number class
int number = random . nextint( 10)； //Randomly generate numbers from 0 to 9.
int user number = 0； //A variable that stores the user number
Boolean symbol = false; //Flag whether to cycle.
While (sign == false) {// loop
user number = random . nextint( 1000)； //Randomly generate numbers from 0 to 999.
sign = checkUserNum(userNumber，number)； //Call the method
}
}
/**
* Check whether the user has won the prize.
* @param userNumber randomly generated user number.
* @param number lottery number
* @return returns yes or no.
*/
public static boolean check usernum(int user number，int number) {
Boolean symbol = false; //Whether winning the prize is marked.
Int firstNum// declares that a variable records hundreds of bits.
Int nextNum// declares that a variable records ten bits.
String buff = new integer (userNumber). toString()； //Convert the user number into a string.
If (buff.length() == 3) {// Judge whether the number of users generated is greater than 100.
first num = integer . parse int(buff . substring(0， 1))； //Intercept hundreds of bits
nextNum = integer . parse int(buff . substring( 1，2))； //Intercept ten digits
If (firstnum-nextnum = = NUMBER) {//If 100 digit minus 10 digit equals the lottery number, the prize will be won.
System.out.println ("lottery number is"+number);
System.out.println ("winning user number is"+buff);
Symbol = true;
}
}
Return flag; //Return
}
Running results:
The lottery number is: 2
The winning user number is: 427
The lottery number is: 7
The winning user number is: 8 16.