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Colby Work
20,422 PointsHow come both variables need to be printed to cause increment?
If I type:
int a = 1
printf("a %d", a);
int b = a++
printf("b %d", b);
it comes out printing 1 both times, but if I enter:
printf("a %d b %b", a, b)
i get a 1 b 2
1 Answer
J.D. Sandifer
18,813 PointsAre you sure you don't mean "i get a 2 b 1"?
The ++ operator can be either before the variable (auto increment) or after (increment). The difference is when the variable is incremented by 1 - before or after any operations on the same line.
Here's a play by play of the code:
int a = 1; // a equals 1
printf("a %d", a); // prints "a 1"
int b = a++; // b equals 1, *after that* a is incremented to 2
printf("b %d", b); // prints "b 1"
printf("a %d b %d", a, b);
// if you add this line it reads "a 2 b 1"