javascript - difference between a++ and ++a in while loop -


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i trying figure out, why end different outcome, when use a++ versus ++a in while loop? know postfix , prefix operations still not why getting results get

var = 1;  while (a < 3) {      console.log(a);     a++;

}

i ger results: 1, 2, 2 , when using ++a instead of a++ different outcome.

 var = 1;  while (a < 3) {          console.log(a);         ++a;   }

in case 1,2,3. can explain operations order step step , why output get?

you'll 1,2,2 or 1,2,3 if run in console - outside console both output 1,2 - check console when running fiddle

when running in console, last number see in console "result" of last operation ... so, 2 (because of post increment) in first case, , 3 (because of pre increment) in second -

if add 1 line after } a; - both show 1,2,3 - so

var = 1;  while (a < 3) {      console.log(a);     a++; } a;

and

var = 1; while (a < 3) {       console.log(a);      ++a; } a;

shows same after while loop finishes


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