/in/foo.cc: In function 'int main()':
/in/foo.cc:19:9: error: 'd' was not declared in this scope
         d[m]=n; 
         ^
/in/foo.cc:25:11: error: 'd' was not declared in this scope
     while(d[p]>m)
           ^
/in/foo.cc:29:21: error: 'd' was not declared in this scope
         double ans=(d[x]*(x-r)-d[i]*(i-r))*1.0/(d[i]-d[x]);
                     ^