Compilare: main.cpp:2:47: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] using namespace std;int v[3000001],a,b,n;main(){freopen("sdo.in","r",stdin);freopen("sdo.out","w",stdout);scanf("%d%d",&a,&b);n=a;while(a--)scanf("%d",&v[a+1]);nth_element(v+1,v+b,v+n+1);printf("%d",v[b]);return 0;} ^ main.cpp: In function 'int main()': main.cpp:2:76: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;int v[3000001],a,b,n;main(){freopen("sdo.in","r",stdin);freopen("sdo.out","w",stdout);scanf("%d%d",&a,&b);n=a;while(a--)scanf("%d",&v[a+1]);nth_element(v+1,v+b,v+n+1);printf("%d",v[b]);return 0;} ^ main.cpp:2:106: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;int v[3000001],a,b,n;main(){freopen("sdo.in","r",stdin);freopen("sdo.out","w",stdout);scanf("%d%d",&a,&b);n=a;while(a--)scanf("%d",&v[a+1]);nth_element(v+1,v+b,v+n+1);printf("%d",v[b]);return 0;} ^ main.cpp:2:126: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;int v[3000001],a,b,n;main(){freopen("sdo.in","r",stdin);freopen("sdo.out","w",stdout);scanf("%d%d",&a,&b);n=a;while(a--)scanf("%d",&v[a+1]);nth_element(v+1,v+b,v+n+1);printf("%d",v[b]);return 0;} ^ main.cpp:2:160: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] using namespace std;int v[3000001],a,b,n;main(){freopen("sdo.in","r",stdin);freopen("sdo.out","w",stdout);scanf("%d%d",&a,&b);n=a;while(a--)scanf("%d",&v[a+1]);nth_element(v+1,v+b,v+n+1);printf("%d",v[b]);return 0;} ^