What is the difference between x++ and ++x [duplicate]

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Incrementing in C++ - When to use x++ or ++x?

What is the difference between x++ and ++x ?

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x++ executes the statement and then increments the value.

++x increments the value and then executes the statement.

var x = 1;
var y = x++; // y = 1, x = 2
var z = ++x; // z = 3, x = 3

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x++ returns x, then increments it.

++x increments x, then returns it.

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++x is higher in the order of operations than x++. ++x happens prior to assignments, but x++ happens after assignments.

For exmaple:

var x = 5;
var a = x++;
// now a == 5, x == 6

And:

var x = 5;
var a = ++x;
// now a == 6, x == 6

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If you write y = ++x, the y variable will be assigned after incrementing x.
If you write y = x++, the y variable will be assigned before incrementing x.

If x is 1, the first one will set y to 2; the second will set y to 1.