Compilare: main.cpp: In function 'void preCalc()': main.cpp:33:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=2; i<s.size(); i++){ ~^~~~~~~~~ main.cpp:40:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=3; i<s.size(); i++){ ~^~~~~~~~~ main.cpp: In function 'int main()': main.cpp:114:17: warning: variable 'temp' set but not used [-Wunused-but-set-variable] int temp=10*(s[i+1]-'0')+s[i+2]-'0'; ^~~~