TANKX Superku And Petra.
using the way the Petra taught to me, worked!
Code:
vec_for_min(my.min_x, my);
	vec_for_max(my.max_x, my);
	printf("%d",(long)my.max_x*2); //its work

Please! Use easy words to be translated. because my English is not very good! Grateful.
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