trading.cpp:21:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
21 | main(){
| ^
trading.cpp: In function 'int main()':
trading.cpp:32:9: warning: unused variable 'h' [-Wunused-variable]
32 | int h=0;
| ^
trading.cpp:12:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
12 | #define scan2(a,b) scanf("%lld %lld",&a, &b);
| ~~~~~^~~~~~~~~~~~~~~~~~~~
trading.cpp:23:5: note: in expansion of macro 'scan2'
23 | scan2(n,m)
| ^~~~~
trading.cpp:13:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
13 | #define scan3(a,b,c) scanf("%lld %lld %lld",&a,&b,&c);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
trading.cpp:27:9: note: in expansion of macro 'scan3'
27 | scan3(l,r,x)
| ^~~~~