euler totient function added

Author: xenowits

Math/EulerTotientFunction/eulerFunction.cpp

@@ -0,0 +1,23 @@
+#include <iostream>
+using namespace std;
+
+int phi(int n) {
+    int result = n;
+    for (int i = 2; i * i <= n; i++) {
+        if(n % i == 0) {
+            while(n % i == 0)
+                n /= i;
+            result -= result / i;
+        }
+    }
+    if(n > 1)
+        result -= result / n;
+    return result;
+}
+
+int main()
+{
+  int n;
+  cin >> n;
+  cout << "The number of coprimes less than n are " << phi(n) << endl;
+}