运行 ID: 129544

Main.cc: In function ‘int main()’:
Main.cc:7:25: error: ‘pow’ was not declared in this scope
  for(j=1;j<=i;j++) s+=a*pow(10,j-1);
                         ^~~
Main.cc:7:25: note: suggested alternative: ‘putw’
  for(j=1;j<=i;j++) s+=a*pow(10,j-1);
                         ^~~
                         putw