Create 4. Match expressions and results

Week 1: Types, condition clauses and loops/4. Match expressions and results

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+Java's basic types
+Type	Saved information	Number range
+byte	integer	1 byte
+short	integer	2 bytes
+char	character	One Unicode-system character
+int	    integer	4 bytes
+long	integer	8 bytes
+float	floating point number (i.e decimal number)	4 bytes
+double	floating point number	8 bytes
+
+
+eg
+public class Example {
+    public static void main(String[] args) {
+        String name = "Mike Madeup";
+        int age = 23;
+        double height = 171.25;
+    }
+}
+
+
+
+eg
+// boolean (IN LOWERCASE) - true, false
+public class Example {
+    public static void main(String[] args) {
+        boolean True = true;
+        boolean False = false;
+        boolean first_larger = 10 > 3;
+
+        System.out.println(first_larger);
+    }
+}
+Output:
+true
+
+
+
+
+eg
+public class Example {
+    public static void main(String[] args) {
+        int first = 23;
+        int second = 10;
+
+        int multiply = first * second;
+        int sum = first + second;
+
+        int largeNum = (first + second) * 100;
+
+        System.out.println(multiply);
+        System.out.println(sum);
+        System.out.println(largeNum); 
+    }
+}
+Output:
+230
+33
+3300
+
+
+
+
+
+
+
+eg
+//If there are several different types involved in an expression, the type of the result is determined by the "largest" type, for example:
+
+public class Example {
+    public static void main(String[] args) {
+        int integer = 10;
+        double float = 5.0;
+
+        System.out.println(integer * 2);
+        System.out.println(float * 2);
+        System.out.println(integer * 2.0);
+        System.out.println(integer + integer);
+        System.out.println(integer + float);
+    }
+}
+Output:
+20
+10.0
+20.0 // int * float -> float
+20
+15.0 //int + float -> float
+
+
+
+
+
+
+eg
+//division
+public class Example {
+    public static void main(String[] args) {
+        System.out.println(5 / 2);
+        System.out.println(5 / 2.0);
+        System.out.println(5.0 / 2);
+        System.out.println(5.0 / 2.0);
+    }
+}
+Output:
+2      // int/int -> int
+2.5    // int/float -> float
+2.5    // float/int -> float
+2.5    // float/float -> float
+
+
+
+
+
+
+eg
+public class Example {
+    public static void main(String[] args) {
+        int divided = 10;
+        int divisor = 4;
+
+        // This returns and integer...
+        System.out.println(divided / divisor);
+
+        // Result is wrong here too...
+        double divide = divided / divisor;
+        System.out.println(divide);
+
+        //...but this works:
+        System.out.println(divided * 1.0 / divisor);
+    }
+}
+Output:
+2     // int/int -> int (rounded down)
+2.0   // int/int -> int (rounded down) -> then convert to double
+2.5   // 'new' double/int -> double
+
+
+
+
+
+eg
+2 * (3 - 1)     4 
+6/4             1 
+2 * 3.0 + 1     7.0
+2.0 * (3.0 - 1.0)   4.0
+2 * 3 + 1       7
+2 * (3 + 1)     8
+2 * (3.0 + 1)   8.0
+6/(2*2.0)       1.5
+
+
+
+