foo.cc: In function 'int main()':
foo.cc:148:21: warning: unused variable 'deep' [-Wunused-variable]
  148 |                 int deep=1,cnt,deepest=0;
      |                     ^~~~
foo.cc:148:28: warning: unused variable 'cnt' [-Wunused-variable]
  148 |                 int deep=1,cnt,deepest=0;
      |                            ^~~
foo.cc:117:13: warning: unused variable 'deep' [-Wunused-variable]
  117 |         int deep=1,cnt,deepest=0;
      |             ^~~~
foo.cc:117:20: warning: unused variable 'cnt' [-Wunused-variable]
  117 |         int deep=1,cnt,deepest=0;
      |                    ^~~
foo.cc:124:17: warning: variable 'y' set but not used [-Wunused-but-set-variable]
  124 |         int x=0,y;
      |                 ^
foo.cc: In function 'int ifrepeat(int, int)':
foo.cc:83:1: warning: control reaches end of non-void function [-Wreturn-type]
   83 | }
      | ^
foo.cc: In function 'int main()':
foo.cc:168:28: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  168 |         */      cout<<x*ksm(y,mod-2)%mod;
      |                         ~~~^~~~~~~~~

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