151 lines
2.2 KiB
Markdown
151 lines
2.2 KiB
Markdown
1.
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```rust
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fn main() {
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let x: i32 = 5;
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let mut y = 5;
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y = x;
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let z = 10; // type of z : i32
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}
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```
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2.
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```rust
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fn main() {
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let v: u16 = 38_u8 as u16;
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}
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```
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3.
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```rust
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fn main() {
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let x = 5;
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assert_eq!("i32".to_string(), type_of(&x));
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}
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// get the type of given variable, return a string representation of the type , e.g "i8", "u8", "i32", "u32"
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fn type_of<T>(_: &T) -> String {
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format!("{}", std::any::type_name::<T>())
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}
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```
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4.
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```rust
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fn main() {
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assert_eq!(i8::MAX, 127);
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assert_eq!(u8::MAX, 255);
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}
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```
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5.
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```rust
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fn main() {
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let v1 = 247_u8 + 8;
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let v2 = i8::checked_add(119, 8).unwrap();
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println!("{},{}",v1,v2);
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}
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```
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6.
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```rust
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fn main() {
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let v = 1_024 + 0xff + 0o77 + 0b1111_1111;
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assert!(v == 1597);
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}
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```
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7.
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```rust
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fn main() {
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let x = 1_000.000_1; // f64
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let y: f32 = 0.12; // f32
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let z = 0.01_f64; // f64
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assert_eq!(type_of(&x), "f64".to_string());
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println!("Success!");
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}
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fn type_of<T>(_: &T) -> String {
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format!("{}", std::any::type_name::<T>())
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}
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```
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8.
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```rust
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fn main() {
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assert!(0.1_f32+0.2_f32==0.3_f32);
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}
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```
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```rust
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fn main() {
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assert!((0.1_f64+ 0.2 - 0.3).abs() < 0.001);
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}
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```
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9.
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```rust
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fn main() {
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let mut sum = 0;
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for i in -3..2 {
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sum += i
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}
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assert!(sum == -5);
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for c in 'a'..='z' {
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println!("{}",c as u8);
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}
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}
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```
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10.
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```rust
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use std::ops::{Range, RangeInclusive};
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fn main() {
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assert_eq!((1..5), Range{ start: 1, end: 5 });
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assert_eq!((1..=5), RangeInclusive::new(1, 5));
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}
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```
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11.
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```rust
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fn main() {
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// Integer addition
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assert!(1u32 + 2 == 3);
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// Integer subtraction
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assert!(1i32 - 2 == -1);
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assert!(1i8 - 2 == -1);
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assert!(3 * 50 == 150);
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assert!(9 / 3 == 3); // error ! make it work
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assert!(24 % 5 == 4);
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// Short-circuiting boolean logic
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assert!(true && false == false);
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assert!(true || false == true);
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assert!(!true == false);
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// Bitwise operations
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println!("0011 AND 0101 is {:04b}", 0b0011u32 & 0b0101);
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println!("0011 OR 0101 is {:04b}", 0b0011u32 | 0b0101);
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println!("0011 XOR 0101 is {:04b}", 0b0011u32 ^ 0b0101);
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println!("1 << 5 is {}", 1u32 << 5);
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println!("0x80 >> 2 is 0x{:x}", 0x80u32 >> 2);
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}
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```
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