Compilare: main.cpp: In function 'int eval()': main.cpp:13:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (p<s.size() && (s[p]=='+' || s[p]=='-')) { ~^~~~~~~~~ main.cpp: In function 'int termen()': main.cpp:23:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (p<s.size() && (s[p]=='*' || s[p]=='/')) { ~^~~~~~~~~ main.cpp: In function 'int fact()': main.cpp:35:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (p<s.size() && s[p]>='0' && s[p]<='9') { ~^~~~~~~~~