implemented function for determining string length of hex string

src/conversionOfNumbers/conversionOfNumbers.c

@@ -51,6 +51,18 @@ unsigned int convertBinaryStrToInt(char* input){
     return result;
 }
 
+int hexStrLen(int input){
+    int length = 0;
+    if(input == 0) return 1;
+    for (int x = 0; x <= input; x++){
+        if(pow(16,x) >= input + 1){
+            length += x;
+            break;
+            }
+        }
+    return length;
+}
+
 char* convertIntToHex(int input){
     int length = 1;
     int rest;