1 files changed, 38 insertions, 0 deletions

diff --git a/src/talks/wasm/examples/4-primes-sieve/script.js b/src/talks/wasm/examples/4-primes-sieve/script.js
new file mode 100644
index 0000000..8041e5b
--- /dev/null
+++ b/src/talks/wasm/examples/4-primes-sieve/script.js
@@ -0,0 +1,38 @@
+import Primes from "./primes.mjs";
+
+var primes = await Primes();
+
+var input = document.getElementById("input");
+var wasm_button = document.getElementById("wasmButton");
+var js_button = document.getElementById("jsButton");
+var resultText = document.getElementById("resultText");
+
+var count_wasm = (n) => primes._count(n);
+
+var count_js = (n) => {
+        if (n < 2)
+                return 0;
+
+        var notprime = new Uint8Array(n+2);
+
+        var count = 0;
+        for (var i = 2; i < n; i++) {
+                count += 1 - notprime[i];
+                for (var j = 2*i; j < n; j += i)
+                        notprime[j] = 1;
+        }
+
+        return count;
+}
+
+var timerun = (count, tag) => {
+        var n = Number(input.value);
+        var msg = "Counting primes less than " + n + " with " + tag;
+        console.time(msg);
+        var c = count(n);
+        console.timeEnd(msg);
+        resultText.innerText = "There are " + c + " primes less than " + n;
+}
+
+wasm_button.addEventListener("click", () => timerun(count_wasm, "WASM"));
+js_button.addEventListener("click", () => timerun(count_js, "JS"));