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use std::io::{self, Read};

fn parse_digits(s: &str) -> Vec<u8> {
    s.bytes().map(|b| b - b'0').collect()
}

fn main() {
    let mut input = String::new();
    io::stdin().read_to_string(&mut input).unwrap();

    let mut lines = input.lines();

    let a = parse_digits(lines.next().unwrap());
    let b = parse_digits(lines.next().unwrap());
    let c = parse_digits(lines.next().unwrap());
    let n = a.len();

    let mut offset = 0;
    let mut local_counter = 0;
    let mut result: u64 = 0;

    for i in (0..n).rev() {
        let dig_a = a[i];
        let dig_b = b[i];
        let dig_c = c[i];

        if offset == 0 {
            if dig_a + dig_b == dig_c {
                local_counter += 1;
            } else if (dig_a + dig_b) % 10 == dig_c {
                offset = 1;
            } else {
                result += local_counter * (local_counter + 1) / 2;
                offset = 0;
                local_counter = 0;
            }
        } else if dig_a + dig_b + offset == dig_c {
            local_counter += 1;
            offset = 0;
        } else if (dig_a + dig_b + offset) % 10 == dig_c {
            offset = 1;
        } else if dig_a + dig_b == dig_c {
            result += local_counter * (local_counter + 1) / 2;
            local_counter = 1;
            offset = 0;
        } else if (dig_a + dig_b) % 10 == dig_c {
            result += local_counter * (local_counter + 1) / 2;
            local_counter = 0;
            offset = 1;
        } else {
            result += local_counter * (local_counter + 1) / 2;
            local_counter = 0;
            offset = 0;
        }
    }

    result += local_counter * (local_counter + 1) / 2;

    println!("{result}");
}