diff --git a/src/main.rs b/src/main.rs
index 20e0e4e..7e6820d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -9,8 +9,13 @@ fn main() {
     println!("t 2nd: {}", t.1);
 
     let mut x: i32 = 10; 
+    let mut z: i32 = 5; 
     println!("x: {x}");
-    let ref_x: &mut i32 = &mut x;
+    println!("z: {z}");
+    let mut ref_x: &mut i32 = &mut x;
     *ref_x = 20; 
     println!("x: {x}");
+    ref_x = &mut z;
+    *ref_x = 20; 
+    println!("z: {z}");
 }
diff --git a/target/debug/basics00 b/target/debug/basics00
index c65d151..c294868 100755
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/4qlgwb3loiguc5oq.o b/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/4qlgwb3loiguc5oq.o
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/1flo4x0vfn957dou.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/1flo4x0vfn957dou.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/20g1uh68tfrguypa.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/20g1uh68tfrguypa.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/220p8y8jth3f7nrz.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/220p8y8jth3f7nrz.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/2bu1z933r12o9ili.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/2bu1z933r12o9ili.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/2cumrsybhfasw9r6.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/2cumrsybhfasw9r6.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/2gp67l902c2vomm6.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/2gp67l902c2vomm6.o
similarity index 100%
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rename to target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/2gp67l902c2vomm6.o
diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/2oz5c3a1wkrjyhl3.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/2oz5c3a1wkrjyhl3.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/3ff68b9qa7oq14ky.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/3ff68b9qa7oq14ky.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/4cmoc6e8dohuin6f.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/4cmoc6e8dohuin6f.o
similarity index 100%
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rename to target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/4cmoc6e8dohuin6f.o
diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/4dt7i4jah93gytlu.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/4dt7i4jah93gytlu.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/4qlgwb3loiguc5oq.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/4qlgwb3loiguc5oq.o
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/dep-graph.bin b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/dep-graph.bin
similarity index 72%
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index 924f74c..ff6a073 100644
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/mwaxihrequg68jr.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/mwaxihrequg68jr.o
similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/query-cache.bin b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/query-cache.bin
similarity index 89%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2-127bw6i2v2gsi/sli8xutquvhkisc.o b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b-1nco2h5zi5c8u/sli8xutquvhkisc.o
similarity index 100%
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similarity index 100%
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diff --git a/target/debug/incremental/basics00-12w982f9njolw/s-gha9mhk8b7-1aoynh2.lock b/target/debug/incremental/basics00-12w982f9njolw/s-ghaaul8ufg-uadb5b.lock
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