Compilare: user.cpp: In function ‘void readFile()’: user.cpp:28:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &n); ^ user.cpp:32:64: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d%d", &xx, &yy), x[xx % 2] ++, y[yy % 2] ++; ^