1st commit on 123_node

2 files changed, 51 insertions, 0 deletions

diff --git a/challenge-123/stuart-little/node/ch-1.js b/challenge-123/stuart-little/node/ch-1.js
new file mode 100755
index 0000000000..5ada161822
--- /dev/null
+++ b/challenge-123/stuart-little/node/ch-1.js
@@ -0,0 +1,26 @@
+#!/usr/bin/env node
+
+// run <script> <number $n> to return the first $n ugly numbers
+
+let memo = new Set([1,2,3,5])
+
+function smth5p(n) {
+    if (memo.has(n)) {return true}
+    for (let prm of [2,3,5]) {
+	if (n%prm===0 && memo.has(n/prm)) {
+	    memo.add(n)
+	    return true
+	}
+    }
+    return false
+}
+
+let count=0
+let nr=0
+while (count < parseInt(process.argv[2])) {
+    nr++
+    if (smth5p(nr)) {
+	count++
+	console.log(nr)
+    }    
+}
diff --git a/challenge-123/stuart-little/node/ch-2.js b/challenge-123/stuart-little/node/ch-2.js
new file mode 100755
index 0000000000..0611520f33
--- /dev/null
+++ b/challenge-123/stuart-little/node/ch-2.js
@@ -0,0 +1,25 @@
+#!/usr/bin/env node
+
+// run <script> <x1 y1 x2 y2 ..>
+
+function sqDist(coords) {
+    return (coords[2]-coords[0])**2 + (coords[3]-coords[1])**2
+}
+
+function sqDistHash(coords) {
+    let hsh={};
+    [0,1,2].forEach( function(i) {
+	[0,1,2,3].slice(i+1).forEach( function(j) {
+	    let dst = sqDist([2*i,2*i+1,2*j,2*j+1].map(ix => coords[ix]))
+	    hsh[dst] = hsh[dst] ? hsh[dst]+1 : 1
+	})
+    })
+    return hsh
+}
+
+function isSq(coords) {
+    const freqs = Object.values(sqDistHash(coords))
+    return freqs.includes(2) && freqs.includes(4)
+}
+
+console.log(isSq(process.argv.slice(2,10).map(x => parseFloat(x))) ? 1 : 0)