Update 2280-minimum-lines-to-represent-a-line-chart.js

Author: everthis

2280-minimum-lines-to-represent-a-line-chart.js

@@ -1,3 +1,33 @@
+/**
+ * @param {number[][]} stockPrices
+ * @return {number}
+ */
+const minimumLines = function(stockPrices) {
+  let res = 1
+  const n = stockPrices.length
+  if(n === 1) return 0
+  stockPrices.sort((a, b) => a[0] - b[0])
+  for(let i = 2; i < n; i++) {
+    const cur = stockPrices[i], p = stockPrices[i - 1], pp = stockPrices[i - 2]
+    if(chk(pp, p, cur)) continue
+    else res++
+  }
+  
+  
+  return res
+};
+
+function chk(p1, p2, p3) {
+  const bi = BigInt
+  // (y3 - y1) / (x3 - x1) == (y2 - y1) / (x2 - x1)
+  const [x1, y1] =  p1, [x2, y2] = p2, [x3, y3] = p3
+  return (bi(y3) - bi(y1)) * (bi(x2) - bi(x1)) === (bi(y2) - bi(y1)) * (bi(x3) - bi(x1))
+}
+
+
+
+// another
+
 /**
  * @param {number[][]} stockPrices
  * @return {number}