1. (a> b) a:? B: If the brackets is true, it returns a, b false returns.
. 2 && / || and & / | difference: when using false && test is skipped if it is left to the right of inspection, direct returns false, increase efficiency; the same token, || returns true test to the left directly to true; & and | can be bit computing, the latter can not.
3. Keyboard Input: steps of: a leader packet: import java.util.scanner; b create objects / tools Scanner sc = new Scanner (System.in); c obtaining data int x = sc.nextInt ();...
Difference ** nextLine () and next () is: nextLine () will absorb input carriage return, the next () will not accept a carriage return and tab **
4. randomly generated functions: Math.random () returns a value double, in the range [0.0, 1.0]
Math among the commonly used functions:
The Math.abs absolute value function ();
The Math.sqrt square root function ();
Math.round rounding function (); ---- four banker's rounding, when applied to the five parameters of 0.5 (e.g. 2.5 becomes 3, becomes -2.5 -2)
5.string type conversion char type:
String start;
char[] a=start.toCharArray();
6.char-Type string type:
String result= String.valueof(a);
7. The operator priority: monocular bit multiplication and division relationship, logic evaluation after three head.