Compilare: main.cpp: In function 'void backtrack(int)': main.cpp:66:13: warning: unused variable 'value1' [-Wunused-variable] 66 | int value1=-1; | ^~~~~~ main.cpp:67:13: warning: unused variable 'value2' [-Wunused-variable] 67 | int value2=-1; | ^~~~~~ main.cpp: In function 'int main()': main.cpp:106:29: warning: array subscript has type 'char' [-Wchar-subscripts] 106 | if(!f1[v1[i]]){ | ~~~~^ main.cpp:107:28: warning: array subscript has type 'char' [-Wchar-subscripts] 107 | f1[v1[i]]=1; | ~~~~^ main.cpp:118:28: warning: array subscript has type 'char' [-Wchar-subscripts] 118 | if(!f2[v2[i]]){ | ~~~~^ main.cpp:119:28: warning: array subscript has type 'char' [-Wchar-subscripts] 119 | f2[v2[i]]=1; | ~~~~^