Compilare: main.cpp: In function 'int main()': main.cpp:15:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<s1.size();++i) ~^~~~~~~~~~ main.cpp:17:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<s2.size();++i) ~^~~~~~~~~~ main.cpp:28:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(k<s1.size() and s1[k]!=s2[0]) ~^~~~~~~~~~ main.cpp:34:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=k+1;j<s1.size();++j) ~^~~~~~~~~~ main.cpp:38:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=1;j<s2.size();++j) ~^~~~~~~~~~