Compilare: main.cpp: In function 'void precalc()': main.cpp:21:36: warning: iteration 1000003 invokes undefined behavior [-Waggressive-loop-optimizations] sum[i] = sum[i - 1] + phi[i]; ~~~~~^ main.cpp:18:23: note: within this loop for (int i = 2; i <= MAX; ++i) { ^ main.cpp:16:16: warning: iteration 1000003 invokes undefined behavior [-Waggressive-loop-optimizations] phi[i] = i - 1; ~~~~~~~^~~~~~~ main.cpp:15:23: note: within this loop for (int i = 2; i <= MAX; ++i) ^