Some tips for improving algorithmic efficiency

1, good at writing variable scope, the use of variables released in time

{

int a = 0;

A range of operations

}//When executed here, a in curly braces is released.

2, the former self-increase self-reduction is slightly higher than the self-reduction efficiency.

++i Efficiency > i++

-I. Efficiency > i--

3. if (conditional expression)

A, the conditional expression here can be calculated first, get a result, put into if () parentheses inside;

B, can also be placed directly inside ()

Recommendation: where appropriate, conditional expressions are placed directly inside the parentheses () because: (The circuit breaker of a logical operation expression ^_^)

Logical Expression,&& | | , sometimes the left-hand value can represent the value of the entire expression, and the expression on the right is no longer calculated, saving time.

4, can use 1 if to try not to use 2 if

Such as: can use

if () {}

else {}

Or

if () {}

else if () {}

else {} Try not to use

if () {}

if () {}

Because, 2 if is to judge 2 times, and if (else if) else structure only need to judge a condition satisfies, other condition not to judge.

Some tips for improving algorithmic efficiency