Compilare: user.cpp: In function ‘int main()’: user.cpp:81:41: warning: suggest parentheses around comparison in operand of ‘^’ [-Wparentheses] if (xorsum[idx] ^ xorsum[i - 1] == sol) { ^ user.cpp: In function ‘int query(int, int)’: user.cpp:51:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:81:36: warning: ‘idx’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (xorsum[idx] ^ xorsum[i - 1] == sol) { ^