Compilare: main.cpp: In function 'int main()': main.cpp:50:34: warning: NULL used in arithmetic [-Wpointer-arith] 50 | if(sol[j] != NULL) | ^~~~ main.cpp:53:34: warning: converting to non-pointer type 'char' from NULL [-Wconversion-null] 53 | sol[j - 1] = NULL; | ^~~~ main.cpp:72:34: warning: NULL used in arithmetic [-Wpointer-arith] 72 | if(sol[j] != NULL) | ^~~~ main.cpp:74:34: warning: converting to non-pointer type 'char' from NULL [-Wconversion-null] 74 | sol[j - 1] = NULL; | ^~~~ main.cpp:98:28: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare] 98 | if(strlen(sol) != n) | ~~~~~~~~~~~~^~~~