mars.cpp: In function 'void dfs(int, int, int)':
mars.cpp:11:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
11 | if(i < m.size() - 1) dfs(i+1, j, z);
| ~~^~~~~~~~~~~~~~
mars.cpp:12:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
12 | if(j < m.size() - 1) dfs(i, j+1, z);
| ~~^~~~~~~~~~~~~~
mars.cpp: In function 'std::string process(std::vector<std::vector<std::__cxx11::basic_string<char> > >, int, int, int, int)':
mars.cpp:57:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
57 | for(int i = 0; i < grid.size(); i ++){
| ~~^~~~~~~~~~~~~
mars.cpp:58:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
58 | for(int j = 0; j < grid[i].size(); j ++){
| ~~^~~~~~~~~~~~~~~~
mars.cpp:65:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
65 | for(int i = 0; i < v.size(); i ++){
| ~~^~~~~~~~~~
mars.cpp:66:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
66 | for(int j = 0; j < v[i].size(); j ++){
| ~~^~~~~~~~~~~~~