supertrees.cpp: In function 'void build(std::vector<std::vector<int> >)':
supertrees.cpp:18:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
18 | for (int i = 0; i < a.size(); i ++) {
| ~~^~~~~~~~~~
supertrees.cpp:19:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
19 | for (int j = 0; j < a[i].size(); j ++) {
| ~~^~~~~~~~~~~~~
supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:63:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
63 | for (j = 1; j < v.size(); j ++) {
| ~~^~~~~~~~~~
supertrees.cpp:85:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
85 | for (j = 1; j < v.size(); j ++) {
| ~~^~~~~~~~~~
/usr/bin/ld: /tmp/ccT264U3.o: in function `build(std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >)':
grader.cpp:(.text+0x320): multiple definition of `build(std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >)'; /tmp/ccYKe3O2.o:supertrees.cpp:(.text+0x1d0): first defined here
collect2: error: ld returned 1 exit status