Valid java code

[wicherh]

This is a pretty stupid question but a equation example: (1 = 1) returns 1 or 0 right so why would this not work?:

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int right = dir + 1 - 4(dir = 4); 
int left = dir - 1 + 4(dir = 0);

This code calculates right and left dir so i can use after this the code:

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public static int[][] offsets = { { 1, 0 }, { 0, -1 }, { -1, 0 }, { 0, 1 } };
int nx = x + offsets[dir][0];
int ny = y + offsets[dir][1];
int nxr = x + offsets[right][0];
int nyr = y + offsets[right][1];
int nxl = x + offsets[left][0];
int nyl = y + offsets[left][1];

if I use the first code, it says

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";" expected[code]
why does he ask that

[tog]

= is assignment
== is comparison
It's really a bad idea to assign to a variable which is used in the same statement again. You can never know which part of the statement is executed first.
But you actually wanna use modulo (%) for this task.

[brazzy]

This is a pretty stupid question but a equation example: (1 = 1) returns 1 or 0 right so why would this not work?:

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int right = dir + 1 - 4(dir = 4); 
int left = dir - 1 + 4(dir = 0);

Not sure what that code is supposed to do, but it's definitely invalid as long as there is no operator in front of the parentheses. Also, what tog said.

[wicherh]

Yea got right code now with modulo.
If you are at a if statement there stays example

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if (x = 1) 
{
}

X =1 returns a value boolean true or false, 1 or 0.
int right = dir + 1 - 4(dir = 4); means:

int right = dir + 1 - 4 * (if dir = 4(if = true it returns a 1 value)) then the equanation does it -3