用C中的浮点值除法时出错

Question

I want to take the the answer from x_rand / 0,2 and y_rand / 0,2 , and store the answer rounded down to an integer in the variable division_x and division_y :

double x_rand = drand48();
double y_rand = drand48();
int division_x = x_rand / 0,2;
int division_y = y_rand / 0,2;

These are the error messages I get:

breakout.c:95:37: error: expected identifier or '('
        int division_x = x_rand / 0,2;
                                    ^
breakout.c:95:37: error: expected ';' at end of declaration
        int division_x = x_rand / 0,2;
                                    ^
                                    ;
breakout.c:96:37: error: expected identifier or '('
        int division_y = y_rand / 0,2;
                                    ^
breakout.c:96:37: error: expected ';' at end of declaration
        int division_y = y_rand / 0,2;
                                    ^
                                    ;

breakout.c:95:33: error: division by zero is undefined
      [-Werror,-Wdivision-by-zero]
        int division_x = x_rand / 0,2;
                            ^ ~
breakout.c:96:33: error: division by zero is undefined
      [-Werror,-Wdivision-by-zero]
        int division_y = y_rand / 0,2;

Someone please explain this to me.

Answer 1

C does not use European style float representations. You need to use 0.2 , not 0,2 .