nicegift.cpp: In function 'int main()':
nicegift.cpp:47:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(long long i = 0;i<add.size();i++){
~^~~~~~~~~~~
nicegift.cpp:55:31: warning: format '%lld' expects argument of type 'long long int', but argument 2 has type 'std::vector<std::vector<long long int> >::size_type {aka long unsigned int}' [-Wformat=]
printf("%lld\n",ans.size());
~~~~~~~~~~^
nicegift.cpp:56:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(long long i = 0;i<ans.size();i++){
~^~~~~~~~~~~
nicegift.cpp:58:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(long long j = 0;j<ans[i].size();j++){
~^~~~~~~~~~~~~~
nicegift.cpp:9:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%lld%lld",&n,&k);
~~~~~^~~~~~~~~~~~~~~~~~
nicegift.cpp:14:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%lld",&a[i].first);
~~~~~^~~~~~~~~~~~~~~~~~~~