/in/main.c: In function 'main':
/in/main.c:41:20: error: format '%d' expects argument of type 'int *', but argument 3 has type 'int' [-Werror=format=]
         scanf("%s %d",countries[i].name,countries[i].rank);
                    ^
/in/main.c:45:22: error: assignment from incompatible pointer type [-Werror=incompatible-pointer-types]
         nodes[i].left=&nodes[2*i].country;
                      ^
/in/main.c:46:23: error: assignment from incompatible pointer type [-Werror=incompatible-pointer-types]
         nodes[i].right=&nodes[2*i+1].country;
                       ^
cc1: all warnings being treated as errors