Compilare: main.cpp: In function 'int main()': main.cpp:34:25: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 34 | while (nodes.size() < n) /// prim's algorithm | ~~~~~~~~~~~~~^~~ main.cpp:26:26: warning: unused variable 'a' [-Wunused-variable] 26 | int n, x, y, xx, yy, a, b, ind=0, node=0; | ^ main.cpp:26:29: warning: unused variable 'b' [-Wunused-variable] 26 | int n, x, y, xx, yy, a, b, ind=0, node=0; | ^ main.cpp:26:32: warning: unused variable 'ind' [-Wunused-variable] 26 | int n, x, y, xx, yy, a, b, ind=0, node=0; | ^~~