Compilare: main.cpp: In function 'int main()': main.cpp:66:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 66 | if(dr == v[x].size()) { | ~~~^~~~~~~~~~~~~~ main.cpp:72:17: warning: statement has no effect [-Wunused-value] 72 | for(st; st <= dr; st ++) { | ^~ main.cpp:118:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 118 | if(dr == v[x].size()) { | ~~~^~~~~~~~~~~~~~ main.cpp:124:17: warning: statement has no effect [-Wunused-value] 124 | for(st; st <= dr; st ++) { | ^~