1, sequence control: program executed line by line from top to bottom, there is no intermediate judgment, and jump
2, branch control: the program to selectively execute
① single branch
if (conditional expression) {
Block of code;
}
② double branch
if (conditional expression) {
1 block of code;
}
else {
2 block of code;
}
③ multi-branch
if (conditional expression 1) {
1 block of code;
}
else if (conditional expression 2) {
2 block of code;
}
....
else {
N-code block is executed;
}
④ nested branch: In a branching structure and complete another branch nested structure, branched structure which is referred to as the inner branch, the branch structure outside of the outer layer is called a branch. Nested branch is not suitable too, up to no more than 3 layers.
⑤switch branch structure
switch (expression) {
Constant case 1:
Statement block 1;
break;
Constant case 2:
Statement block 2;
break ;
...
default :
default statement block
break ;
}
switch statement expression is a constant expression must be an integer (char, short, int, long, etc.) or enumeration type
Value case clause must be a constant, not a variable
default clause is optional and, when no matching Case, performs default
After a break statement is used in case that the branch executing the program out of the switch statement block
If you do not write break, the next case statement will execute a block, until it encounters a break or executed to the end switch, this phenomenon is called penetration
switch and if the comparison:
If it is determined the specific values is small, and in line with integers, enumerated types, although both statements can be used, it is recommended to use a switch statement
Other cases, the judgment of the interval, the result is true for the false judgment, that use is if, if the wider