Compilare: main.cpp: In function 'int main()': main.cpp:28:18: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare] 28 | for(int i=0;i<strlen(a);i++) | ~^~~~~~~~~~ main.cpp:33:18: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare] 33 | for(int i=0;i<strlen(b);i++) | ~^~~~~~~~~~ main.cpp:46:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 46 | for(int j=0;j<fr_a[i].size();j++) | ~^~~~~~~~~~~~~~~