foo.cc: In function 'int main()':
foo.cc:33:13: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
             if(queue[tail].s==k)
             ^~
foo.cc:35:14: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
              tail++;
              ^~~~
foo.cc:16:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&k);
     ~~~~~^~~~~~~~~~~~~~

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