nicegift.cpp:20:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
20 | main(){
| ^
nicegift.cpp: In function 'int main()':
nicegift.cpp:49:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
49 | for (j=0;j<v[i].size();++j){
| ~^~~~~~~~~~~~
nicegift.cpp:76:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
76 | for (j=0;j<ans[i].size();++j){
| ~^~~~~~~~~~~~~~
nicegift.cpp:10:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
10 | #define scan2(a,b) scanf("%lld %lld",&a, &b);
| ~~~~~^~~~~~~~~~~~~~~~~~~~
nicegift.cpp:22:5: note: in expansion of macro 'scan2'
22 | scan2(n,k)
| ^~~~~
nicegift.cpp:9:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
9 | #define scan1(a) scanf("%lld",&a);
| ~~~~~^~~~~~~~~~~
nicegift.cpp:24:9: note: in expansion of macro 'scan1'
24 | scan1(q[i]);
| ^~~~~