Concatenation str with str

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examples/strings/concatenation-str-with-str/src/main.rs

fn main() {
    let str1 = "Hello";
    let str2 = "World";

    // let text = str1 + str2; // cannot add `&str` to `&str`
    let text = str1.to_string() + " " + str2;
    println!("{}", text);
}

Hello World