Added correction for exo 4

exercice_001/exo4.js

@@ -0,0 +1,67 @@
+document.getElementById("main-title").innerText = "Le Respectable Rectangle";
+
+function isNumber(str) {
+    return str !== "" && !isNaN(str);
+}
+
+function changeHeight() {
+    let inputHeight = document.getElementById("height").value;
+    if(isNumber(inputHeight)){
+        document.getElementById("rect").style.height = inputHeight + 'px';
+    }
+}
+
+function changeWidth() {
+    let inputWidth = document.getElementById("width").value;
+    if(isNumber(inputWidth)){
+        document.getElementById("rect").style.width = inputWidth + 'px';
+    }
+}
+
+function getRectangleWidth() {
+    return document.getElementById("rect").offsetWidth;
+}
+
+function getRectangleHeight() {
+    return document.getElementById("rect").offsetHeight;
+}
+
+function computeArea(width, height) {
+    return width * height;
+}
+
+function computePerimeter(width, height) {
+    return 2 * width + 2 * height;
+}
+
+function setRectangleArea(area) {
+    document.getElementById("area").innerText = area;
+}
+
+function changeArea(){
+    let width = getRectangleWidth();
+    let height = getRectangleHeight();
+    let area = computeArea(width, height);
+    setRectangleArea(area);
+}
+
+function setRectanglePerimeter(perimeter) {
+    document.getElementById("perimeter").innerText = perimeter;
+}
+
+function changePerimeter() {
+    let width = getRectangleWidth();
+    let height = getRectangleHeight();
+    let perimeter = computePerimeter(width, height);
+    setRectanglePerimeter(perimeter);
+}
+
+function changeRectangle(){
+    changeHeight();
+    changeWidth();
+    changeArea();
+
+
+
+    changePerimeter();
+}