Compilare: user.cpp: In function ‘int valid(int, int&)’: user.cpp:50: warning: suggest parentheses around ‘&&’ within ‘||’ user.cpp:71: warning: suggest parentheses around ‘&&’ within ‘||’ user.cpp:104: warning: suggest parentheses around ‘&&’ within ‘||’ user.cpp:124: warning: suggest parentheses around ‘&&’ within ‘||’ user.cpp: In function ‘void back(int, int&)’: user.cpp:170: warning: suggest explicit braces to avoid ambiguous ‘else’ user.cpp: In function ‘int main()’: user.cpp:180: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:183: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int valid(int, int&)’: user.cpp:38: warning: ‘y1’ may be used uninitialized in this function user.cpp:38: warning: ‘y2’ may be used uninitialized in this function user.cpp:38: warning: ‘x1’ may be used uninitialized in this function user.cpp:38: warning: ‘x2’ may be used uninitialized in this function