Compilare: main.cpp: In function 'int main()': main.cpp:11:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s)-1;i++) ~^~~~~~~~~~~~ main.cpp:12:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=i+1;j<strlen(s);j++) ~^~~~~~~~~~ main.cpp:19:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i==strlen(s)-1) ~^~~~~~~~~~~~~