I remember when I was in 'prepa', I was interested in going to a pure programming 'grande ecole', but unfortunately, only ENSIMAG and IIE would qualify (the one

I remember when I was in 'prepa', I was interested in going to a pure programming 'grande ecole', but unfortunately, only ENSIMAG and IIE would qualify (the ones you mentioned have expensive admission fees - by French standards). There are lots of 'grandes ecoles' offering programming, but mixed with Electronics and/or Mechanical Engineering. At the end I went to another 'grande ecole' that was doing maths and statistics, with a few programming courses. Also in France we don't have programming classes in high school (at least not when I was there in the nineties), which I think is/was a waste.