foo.cc: In function 'int main()':
foo.cc:4:17: warning: unused variable 'n' [-Wunused-variable]
    4 |         int s,t,n=1,k;
      |                 ^
foo.cc:4:21: warning: unused variable 'k' [-Wunused-variable]
    4 |         int s,t,n=1,k;
      |                     ^
foo.cc:10:18: warning: 's' is used uninitialized [-Wuninitialized]
   10 |                 s+=300;
      |                 ~^~~~~
foo.cc:4:13: note: 's' was declared here
    4 |         int s,t,n=1,k;
      |             ^
foo.cc:16:26: warning: 't' may be used uninitialized [-Wmaybe-uninitialized]
   16 |                         t+=(s-ans[j])/100*100;
      |                         ~^~~~~~~~~~~~~~~~~~~~
foo.cc:4:15: note: 't' was declared here
    4 |         int s,t,n=1,k;
      |               ^

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