foo.cc: In function 'int main()':
foo.cc:7:2: error: 'len' was not declared in this scope
  len=(int)log10(c)+1;
  ^~~
foo.cc:7:2: note: suggested alternative: 'mblen'
  len=(int)log10(c)+1;
  ^~~
  mblen
foo.cc:7:11: error: 'log10' was not declared in this scope
  len=(int)log10(c)+1;
           ^~~~~
foo.cc:9:3: error: 's' was not declared in this scope
   s[i]=c%10;
   ^
foo.cc:13:6: error: 's' was not declared in this scope
   if(s[i]==1) cout<<"one ";
      ^
foo.cc:14:6: error: 's' was not declared in this scope
   if(s[i]==2) cout<<"two ";
      ^
foo.cc:15:6: error: 's' was not declared in this scope
   if(s[i]==3) cout<<"three ";
      ^
foo.cc:16:6: error: 's' was not declared in this scope
   if(s[i]==4) cout<<"four ";
      ^
foo.cc:17:6: error: 's' was not declared in this scope
   if(s[i]==5) cout<<"five ";
      ^
foo.cc:18:6: error: 's' was not declared in this scope
   if(s[i]==6) cout<<"six ";
      ^
foo.cc:19:6: error: 's' was not declared in this scope
   if(s[i]==7) cout<<"seven ";
      ^
foo.cc:20:6: error: 's' was not declared in this scope
   if(s[i]==8) cout<<"eight ";
      ^
foo.cc:21:6: error: 's' was not declared in this scope
   if(s[i]==9) cout<<"nine ";
      ^

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