Update Functions.java

math-functions/src/main/java/com.bobocode/Functions.java

@@ -14,7 +14,7 @@ public class Functions {
     public static FunctionMap<Integer, Integer> intFunctionMap() {
         FunctionMap<Integer, Integer> intFunctionMap = new FunctionMap<>();
 
-        // todo: add simple functions to the function map (abs, sng, increment, decrement, square)
+        // todo: add simple functions to the function map (abs, sgn, increment, decrement, square)
 
         return intFunctionMap;
     }