Compilare: main.cpp: In constructor 'node::node()': main.cpp:15:8: warning: 'node::par' will be initialized after [-Wreorder] node *par; ^~~ main.cpp:13:6: warning: 'int node::val' [-Wreorder] int val; ^~~ main.cpp:18:2: warning: when initialized here [-Wreorder] node():par(this),val(0),sz(0),ch({this,this}),isrev(0){} ^~~~ main.cpp:18:55: warning: list-initializer for non-class type must not be parenthesized node():par(this),val(0),sz(0),ch({this,this}),isrev(0){} ^ main.cpp: In constructor 'node::node(int, node*, node*, node*)': main.cpp:15:8: warning: 'node::par' will be initialized after [-Wreorder] node *par; ^~~ main.cpp:13:6: warning: 'int node::val' [-Wreorder] int val; ^~~ main.cpp:19:2: warning: when initialized here [-Wreorder] node(int val,node* lf=empty,node *rt=empty,node *par=empty):par(par),val(val),sz(1+lf->sz+rt->sz),ch({lf,rt}),isrev(0){} ^~~~ main.cpp:19:119: warning: list-initializer for non-class type must not be parenthesized node(int val,node* lf=empty,node *rt=empty,node *par=empty):par(par),val(val),sz(1+lf->sz+rt->sz),ch({lf,rt}),isrev(0){} ^ main.cpp: In function 'int main()': main.cpp:173:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("permsort2.in","r",stdin); freopen("permsort2.out","w",stdout); ^ main.cpp:173:72: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("permsort2.in","r",stdin); freopen("permsort2.out","w",stdout); ^ main.cpp:175:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ main.cpp:181:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^