int a, b;
a = 1;
a = a + a++;
a = 1;
b = a + a++;
printf("%d %d, a, b);
output : 3,2
What’s the difference between line 3 and 5?
int a, b; a = 1; a = a + a++; a = 1;
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int a, b;
a = 1;
a = a + a++;
a = 1;
b = a + a++;
printf("%d %d, a, b);
output : 3,2
What’s the difference between line 3 and 5?
What you are doing is undefined.
You can’t change the value of a variable you are about to assign to.
You also can’t change the value of a variable with a side effect and also try to use that same variable elsewhere in the same expression (unless there is a sequence point, but in this case there isn’t). The order of evaluation for the two arguments for + is undefined.
So if there is a difference between the two lines, it is that the first is undefined for two reasons, and line 5 is only undefined for one reason. But the point is both line 3 and line 5 are undefined and doing either is wrong.