Compilare: user.cpp: In function ‘int exp(long long int, long long int)’: user.cpp:10:10: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if(k & 1 == 1) { ^ user.cpp: In function ‘long long int exp2(long long int, long long int, int)’: user.cpp:22:10: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if(k & 1 == 1) { ^ user.cpp: In function ‘int main()’: user.cpp:60:31: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d", &a, &n); ^