Updating the README example.

Author: lemire

README.md

@@ -35,7 +35,7 @@ The implementation does not throw and does not allocate memory (e.g., with `new`
 Example:
 
 ``` C++
-#include "fast_float/parse_number.h"
+#include "fast_float/fast_float.h"
 #include <iostream>
 
 int main() {
@@ -44,6 +44,7 @@ int main() {
     auto answer = fast_float::from_chars(input.data(), input.data()+input.size(), result);
     if(answer.ec != std::errc()) { std::cerr << "parsing failure\n"; return EXIT_FAILURE; }
     std::cout << "parsed the number " << result << std::endl;
+    return EXIT_SUCCESS;
 }
 ```
 

tests/example_test.cpp

@@ -8,4 +8,5 @@ int main() {
     auto answer = fast_float::from_chars(input.data(), input.data()+input.size(), result);
     if(answer.ec != std::errc()) { std::cerr << "parsing failure\n"; return EXIT_FAILURE; }
     std::cout << "parsed the number " << result << std::endl;
+    return EXIT_SUCCESS;
 }