foo.cc: In function 'int main()':
foo.cc:13:10: warning: unused variable 'j' [-Wunused-variable]
   13 |  int n,i,j,flag,index,k;
      |          ^
foo.cc:14:19: warning: unused variable 't' [-Wunused-variable]
   14 |  struct SR rec[N],t;
      |                   ^
foo.cc:19:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 |   scanf("%d%s%s%d",&rec[i].id,rec[i].name,rec[i].phone,&rec[i].secs);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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