diff --git a/191_number_of_1_bits/Cargo.lock b/191_number_of_1_bits/Cargo.lock
new file mode 100644
index 0000000..156d5da
--- /dev/null
+++ b/191_number_of_1_bits/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "number_of_1_bits"
+version = "0.1.0"
diff --git a/191_number_of_1_bits/Cargo.toml b/191_number_of_1_bits/Cargo.toml
new file mode 100644
index 0000000..911a38e
--- /dev/null
+++ b/191_number_of_1_bits/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "number_of_1_bits"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
diff --git a/191_number_of_1_bits/src/main.rs b/191_number_of_1_bits/src/main.rs
new file mode 100644
index 0000000..46d381c
--- /dev/null
+++ b/191_number_of_1_bits/src/main.rs
@@ -0,0 +1,18 @@
+fn main() {
+    println!("Hello, world!");
+}
+
+struct Solution;
+
+impl Solution {
+    pub fn hamming_weight(mut n: i32) -> i32 {
+        let mut result = 0;
+
+        while n > 0 {
+            result += n & 1;
+            n >>= 1;
+        }
+
+        result
+    }
+}