Compilare: main.cpp: In function 'int main()': main.cpp:88:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<=strlen(s); i++){ ~^~~~~~~~~~~ main.cpp:93:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<=strlen(s); j++){ ~^~~~~~~~~~~ main.cpp:101:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<=strlen(s); j++){ ~^~~~~~~~~~~