foo.cc: In function 'int main()':
foo.cc:20:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d %d %d",&L,&s,&t,&n);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:21:5: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i=1;i<=n;scanf("%d",&stone[i]), i++);
     ^~~

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