Compilare: main.cpp: In function 'int main()': main.cpp:88:36: warning: iteration 200137 invokes undefined behavior [-Waggressive-loop-optimizations] nivel[i] = 0, euler[i] = 0, ind[i] = 0, viz[i] = 0, viz2[i] = 0; ~~~~~~~~~^~~ main.cpp:85:38: note: within this loop for ( register int i = 0 ; i <= NMAX ; ++i ) ~~^~~~~~~ main.cpp:56:16: warning: iteration 200135 invokes undefined behavior [-Waggressive-loop-optimizations] lg2[i] = lg2[i / 2] + 1; ~~~~~~~^~~~~~~~~~~~~~~~ main.cpp:55:34: note: within this loop for ( register int i = 2 ; i <= NMAX ; ++i ) ~~^~~~~~~