[Java] When writing the source ... A memorandum of understanding ①

▼ Think carefully about whether variable declarations should be inside or outside the loop ⇒ The shorter the scope, the shorter the processing time of the machine.

▼ Be careful where you say the same thing    int i = a + b;    int sum += i;

           ⇒ int sum += a+b;

Let's summarize the parts that say the same thing!

▼ Think carefully about whether or not it should be an array ⇒ Only when it is necessary to specify "○ th" etc. later and take it out

▼ Variables used for iterative processing


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