 <pre><code>struct A{ union B{ struct C { float x, y, z; } S; float xyz[3]; } U; int a; }; int main () { struct A v = { .U.S.x = 0.0f, .U.S.y = 123.234f, .U.S.z= 123.3f }; struct A w = { .U.xyz = {0.0f, 123.234f, 123.3f} }; printf("\n %f %f %f \n ",v.U.S.x, v.U.S.y ,v.U.S.z); } </code></pre>