footprint.cpp: In function 'int main()':
footprint.cpp:30:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0;i < v.size();i++)
~~^~~~~~~~~~
footprint.cpp:16:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d", &n);
~~~~~^~~~~~~~~~
footprint.cpp:19:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &x[i], &y[i]);
~~~~~^~~~~~~~~~~~~~~~~~~~~~~
footprint.cpp:29:11: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized]
printf("%d %d\n", x[j], y[j]);
~~~~~~^~~~~~~~~~~~~~~~~~~~~~~