diff --git a/exercice_001/exo1.html b/exercice_001/exo1.html
index 0d531c4..2a71e29 100644
--- a/exercice_001/exo1.html
+++ b/exercice_001/exo1.html
@@ -82,10 +82,10 @@
             <button type="button" class="button is-warning" id="button-2" onclick="exo1c()" >#button-2</button>
         </div>
         <div class="column">
-            <button type="button" class="button is-primary is-light" id="button-3">#button-3</button>
+            <button type="button" class="button is-primary is-light" id="button-3" onclick="exo1d()">#button-3</button>
         </div>
         <div class="column">
-            <button type="button" class="button is-warning is-light" id="button-4">#button-4</button>
+            <button type="button" class="button is-warning is-light" id="button-4" onclick="exo1e()">#button-4</button>
         </div>
     </div>
 </div>
diff --git a/exercice_001/exo1.js b/exercice_001/exo1.js
index 76c975f..dde6c41 100644
--- a/exercice_001/exo1.js
+++ b/exercice_001/exo1.js
@@ -17,5 +17,42 @@ function exo1c(){
     let input2 = document.getElementById("input-2").value;
 
     document.getElementById("result-box-2").innerText = getInputEqualityMessage(input1, input2);
+}
 
-}
\ No newline at end of file
+function isNumber(str) {
+    return str !== "" && !isNaN(str);
+}
+
+function getIsNumberMessage(input) {
+    if(isNumber(input)){
+        return "Number!";
+    }
+    return "n'est pas un nombre";
+}
+
+function exo1d(){
+    let input1 = document.getElementById("input-3").value;
+
+    document.getElementById("result-box-3").innerText = getIsNumberMessage(input1);
+}
+
+function getSizeMessage(n) {
+    if(n < 1000){
+        return "plus plus petit que 1000";
+    }
+    return "plus plus grand que 1000";
+}
+
+function getSafeSizeMessage(input) {
+    if(!isNumber(input)){
+        return "n'est pas un nombre";
+    }
+    return getSizeMessage(parseInt(input));
+
+}
+
+function exo1e(){
+    let input1 = document.getElementById("input-4").value;
+
+    document.getElementById("result-box-4").innerText = getSafeSizeMessage(input1);
+}