Compilare: main.cpp: In function 'int main()': main.cpp:32:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < s.size() ; j++) ~~^~~~~~~~~~ main.cpp:36:55: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(s[j] >= '0' && s[j] <= '9' && j < s.size()) ~~^~~~~~~~~~ main.cpp:56:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < s.size() ; j++) ~~^~~~~~~~~~ main.cpp:60:55: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(s[j] >= '0' && s[j] <= '9' && j < s.size()) ~~^~~~~~~~~~ main.cpp:98:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < s.size() ; j++) ~~^~~~~~~~~~ main.cpp:102:55: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(s[j] >= '0' && s[j] <= '9' && j < s.size()) ~~^~~~~~~~~~