const rl = require("readline").createInterface({ input: process.stdin }); var iter = rl[Symbol.asyncIterator](); const readline = async () => (await iter.next()).value; void async function () { // Write your code here while(line = await readline()){ const nums=line.split(' ').map(Number); console.log(s(nums[0],nums[1], nums[2], nums[3], nums[4])) function s(r, x, y, x1, y1){ let d1 = (x1 - x)**2 + (y1-y)**2; var s1 = 0; d = Math.sqrt(d1); if( d%(2*r)===0){ s1 = Math.round(d/(2*r)); }else{ s1 = Math.round(d/(2*r))+1; } return s1; } } }()