Compilare: main.cpp: In function 'void afis()': main.cpp:11:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for(int i=1; i<=N; i++) ^~~ main.cpp:13:9: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' cout<<'\n'; ^~~~ main.cpp: In function 'void backtrack(int)': main.cpp:30:3: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses] if(ok(k)) ^