simplify addrs

tools/addrs.cpp

@@ -1,10 +1,9 @@
 #include <iostream>
 
 int main(void) {
-    int a;
-    int *b = new int;
+    int *a = new int;
     std::cout << "main:  " << uintptr_t(main) << "\n";
     std::cout << "stack: " << uintptr_t(&a) << "\n";
-    std::cout << "heap:  " << uintptr_t(b) << "\n";
-    delete b;
+    std::cout << "heap:  " << uintptr_t(a) << "\n";
+    delete a;
 }