Compilare: user.cpp:97:6: warning: ISO C++ forbids declaration of ‘main’ with no type [-Wreturn-type] main(){ ^ user.cpp: In function ‘void read()’: user.cpp:70:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&N,&K); ^ user.cpp:72:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a[i].fi); ^ user.cpp: In function ‘int main()’: user.cpp:99:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pikachu.in","r",stdin); ^ user.cpp:100:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pikachu.out","w",stdout); ^