Q2.1
Write a Java program that compares two Strings. The two Strings should be inputted using user input.
(i): If the two Strings are exactly the same, a message should be printed to the screen which reads “Exactly the same: True”, otherwise, a message should be printed to the screen which reads “Exactly the same: False”.
(ii): If and only if the first comparison was false, a comparison should be done that ignores case sensitivity. If they are the same, while ignoring the case, a message should be printed to the screen which reads “Similar: True”, otherwise, a message should be printed to the screen which reads “Similar: False”.
package A2018;
import java.util.*;
public class Q21 {
public static void main(String[] args) {
// 1
Scanner in = new Scanner(System.in);
String str1 = in.next();
String str2 = in.next();
in.close();
if (str1.equals(str2)) {
System.out.println("Exactly the same: True");
} else {
System.out.println("Exactly the same: False");
// 2
if (str1.equalsIgnoreCase(str2)) {
System.out.println("Similar: True");
} else {
System.out.println("Similar: False");
}
}
}
}
Q2.2
Write a Java program that will: (i): Create a 2D array of a size that is decided by user input – the first number relates to the number of rows and the second number relates to the number of columns. (ii): Get the user to populate the array with integers. (iii): Print to the screen the total number of odd numbers in the array. (iv): Calculate the sum of all the odd numbers in the array and print the answer to the screen. (v): Print the contents of the array to the screen with each row printed on a line of its own. (v): Determine which row has the largest sum and print this sum to the screen along with the row number.
package A2018;
import java.util.*;
public class Q22 {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
// 1
int row = in.nextInt();
int col = in.nextInt();
int[][] array = new int[row][col];
// 2
for (int i = 0; i < array.length; i++) {
for (int j = 0; j < array[i].length; j++) {
array[i][j] = in.nextInt();
}
}
// 3/4
int sum = 0;
int numood = 0;
for (int i = 0; i < array.length; i++) {
for (int j = 0; j < array[i].length; j++) {
if (array[i][j] % 2 != 0) {
sum += array[i][j];
numood++;
}
}
}
System.out.println(numood);
System.out.println(sum);
// 5
for (int i = 0; i < array.length; i++) {
for (int j = 0; j < array[i].length; j++) {
System.out.print(" " + array[i][j]);
}
System.out.println();
}
// 6
int max = 0;
for (int i = 0; i < array.length; i++) {
int lowsum = 0;
for (int j = 0; j < array[i].length; j++) {
lowsum += array[i][j];
}
if (lowsum > max) {
max = lowsum;
}
}
System.out.println(max);
}
}
Q2.3
Write a Java program that: (i): Asks the user to enter an integer number. (ii): Determines and displays a message to indicate if the given input is an even number or an odd number. (iii): Determines and displays if the number is a prime number. A prime number is a number that is divisible ONLY by itself and 1. If the number is not a prime number the program should output one number that divides in to the inputted number, otherwise it should print a message saying it is not prime and state that it is only divisible by itself and one.
For example, some sample outputs from your program would be as follows:
6 is not a prime number. It is divisible 3.
12 is not a prime number. It is divisible 6.
7 is a prime number as it is only divisible by 1 and 7.
13 is a prime number as it is only divisible by 1 and 13.
package A2018;
import java.util.*;
public class Q23 {
public static void main(String[] args) {
// 1
Scanner in = new Scanner(System.in);
int num = in.nextInt();
in.close();
// 2
if (num % 2 == 0) {
System.out.println("even");
} else {
System.out.println("odd");
}
// 3，内部迭代
boolean flag = false;
for (int i = num-1; i >=0; i--) {//素数判断注意从2开始，不能包括本身
if (num % i == 0) {
System.out.println(num + " is not a prime number.It is divisible " + i);
flag = true;
break;
}
}
if (flag = false) {//这样谢还避免了1的情况
System.out.println(num + " is a prime number as it is only divisible by 1 and " + num);
}
}
}
留言