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README.md

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+# Blue Archive Gacha Simulator 
+
+Here's an implementation of Blue Archive's Gacha System
+I believe it to be correct, though I'm always willing to accept corrections if you have any!
+
+
+## Example
+
+Here's what's needed in order to call `.roll()` and `.roll10()`.
+
+```rust
+let mut file = File::open("students.json").unwrap();
+    let mut json = String::new();
+    file.read_to_string(&mut json).unwrap();
+
+    let students: Vec<Student> = serde_json::from_str(&json).unwrap();
+
+    let banner_students: Vec<Student> = students
+        .iter()
+        .filter(|student| student.name != "ノゾミ")
+        .map(|student| student.clone())
+        .collect();
+
+    let hoshino = find_student(&students, "ホシノ").unwrap();
+    let shiroko = find_student(&students, "シロコ").unwrap();
+    let rate_up_students = vec![shiroko, hoshino];
+
+    let gacha = GachaBuilder::new(79.0, 18.5, 2.5)
+        .with_pool(banner_students)
+        .with_priority(&rate_up_students, 0.7)
+        .finish()
+        .unwrap();
+
+    let pickup_banner = BannerBuilder::new("ピックアップ募集")
+        .with_name_translation(Language::English, "Rate-Up Registration")
+        .with_sparkable_students(&rate_up_students)
+        .with_gacha(&gacha)
+        .finish()
+        .unwrap();
+```