Compilare: user.cpp: In function ‘int main()’: user.cpp:4:91: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zmeu2.in","r",stdin),freopen("zmeu2.out","w",stdout),scanf("%d%d%d",&n,&p,&k); ^ user.cpp:4:91: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:4:91: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:9:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",d+i,c+i); ^ user.cpp:11:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&i,&j),g[i][j]=0; ^ user.cpp:22:23: warning: iteration 10000u invokes undefined behavior [-Waggressive-loop-optimizations] r[i]=1<<30; ^ user.cpp:21:9: note: containing loop for(i=1;i<=40005;i++) ^