foo.cc: In function 'int main()':
foo.cc:49:19: warning: unused variable 'rlen' [-Wunused-variable]
         int T,i,k,rlen,k1;
                   ^~~~
foo.cc:51:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&T);
         ~~~~~^~~~~~~~~
foo.cc:71:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
                 scanf("%lld%lld",&l,&r);
                 ~~~~~^~~~~~~~~~~~~~~~~~