Compilare: main.cpp: In function 'int main()': main.cpp:100:47: warning: array subscript has type 'char' [-Wchar-subscripts] 100 | while(k1>0&&pr[op[k1]]>pr[s[i]]) | ~~~~~^ main.cpp:100:56: warning: array subscript has type 'char' [-Wchar-subscripts] 100 | while(k1>0&&pr[op[k1]]>pr[s[i]]) | ~~~^ main.cpp:106:47: warning: array subscript has type 'char' [-Wchar-subscripts] 106 | while(k1>0 && pr[op[k1]]>=pr[s[i]]) | ~~~~~^ main.cpp:106:57: warning: array subscript has type 'char' [-Wchar-subscripts] 106 | while(k1>0 && pr[op[k1]]>=pr[s[i]]) | ~~~^