'use strict'

function main(s) {

  s = s.split('\n')[0].split(' ').map(n => Number(n));

  const x = s[0];
  const y = s[1];
  const z = s[2];

  const ans = Math.floor((x - z) / (y + z));

  console.log(ans);
}

main(require("fs").readFileSync("/dev/stdin", "utf8"));
