Update CppCoreGuidelines.md

Author: AndrewPardoe

CppCoreGuidelines.md

@@ -16243,7 +16243,7 @@ and should be used only as building blocks for meaningful concepts, rather than
     template<typename T>
     concept Addable = has_plus<T>;    // bad; insufficient
 
-    template<Addable N> auto plus(const N& a, const N& b) // use two numbers
+    template<Addable N> auto algo(const N& a, const N& b) // use two numbers
     {
         // ...
         return a + b;
@@ -16273,19 +16273,19 @@ The ability to specify a meaningful semantics is a defining characteristic of a
                      && has_multiply<T>
                      && has_divide<T>;
 
-    template<Number N> auto plus(const N& a, const N& b) // use two numbers
+    template<Number N> auto algo(const N& a, const N& b) // use two numbers
     {
         // ...
         return a + b;
     }
 
     int x = 7;
     int y = 9;
-    auto z = plus(x, y);   // z = 18
+    auto z = algo(x, y);   // z = 18
 
     string xx = "7";
     string yy = "9";
-    auto zz = plus(xx, yy);   // error: string is not a Number
+    auto zz = algo(xx, yy);   // error: string is not a Number
 
 ##### Note