Compilare: user.cpp: In function ‘int main()’: user.cpp:51:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j; ^ user.cpp:61:9: warning: unused variable ‘left’ [-Wunused-variable] int left=k; ^ user.cpp:52:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("immortal.in","r",stdin); ^ user.cpp:53:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("immortal.out","w",stdout); ^ user.cpp:55:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&m,&k); ^ user.cpp:56:58: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i=1;i<=k;i++) { scanf("%d%d",&rst[i].x,&rst[i].y); camp[rst[i].x][rst[i].y]=1; } ^