foo.cc: In function 'int main()':
foo.cc:16:23: warning: 'r' may be used uninitialized [-Wmaybe-uninitialized]
   16 |         cout<<l<<' '<<r;
      |                       ^
foo.cc:4:21: note: 'r' was declared here
    4 |         int n,m,t,l,r,num=0;
      |                     ^
foo.cc:16:18: warning: 'l' may be used uninitialized [-Wmaybe-uninitialized]
   16 |         cout<<l<<' '<<r;
      |                  ^~~
foo.cc:4:19: note: 'l' was declared here
    4 |         int n,m,t,l,r,num=0;
      |                   ^

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