strange_device.cpp: In function 'void solve()':
strange_device.cpp:36:18: 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]
36 | for(int i=1;i<b.size();i++){
| ~^~~~~~~~~
strange_device.cpp:56:18: 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]
56 | for(int j=0;j<l.size();j++){
| ~^~~~~~~~~
strange_device.cpp:58:16: error: 'i' was not declared in this scope
58 | ans+=r[i]-l[i]+1;
| ^
strange_device.cpp: At global scope:
strange_device.cpp:65:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
65 | main()
| ^~~~
strange_device.cpp: In function 'void solve()':
strange_device.cpp:20:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
20 | scanf("%lld",&a[i].F);
| ~~~~~^~~~~~~~~~~~~~~~
strange_device.cpp:21:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
21 | scanf("%lld",&a[i].S);
| ~~~~~^~~~~~~~~~~~~~~~