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use std::collections::{HashSet, hash_map};
use std::hash::Hash;
use std::io::{self, BufRead, BufWriter};
use std::io::Write;
use std::str;
use std::collections::{HashMap};
use std::cmp::{max,min};
use std::mem::{swap};

/// https://github.com/EbTech/rust-algorithms/blob/master/src/scanner.rs
pub struct Scanner<R> {
    reader: R,
    buffer: Vec<String>,
}

impl<R: io::BufRead> Scanner<R> {
    pub fn new(reader: R) -> Self {
        Self {
            reader,
            buffer: vec![],
        }
    }

    pub fn token<T: str::FromStr>(&mut self) -> T {
        loop {
            if let Some(token) = self.buffer.pop() {
                return token.parse().ok().expect("Failed parse");
            }
            let mut input = String::new();
            self.reader.read_line(&mut input).expect("Failed read");
            self.buffer = input.split_whitespace().rev().map(String::from).collect();
        }
    }
}


fn main() {
    let mut scan = Scanner::new(io::stdin().lock());
    let a = scan.token::<String>();
    let b = scan.token::<String>();
    let c = scan.token::<String>();

    let v = a.as_bytes().iter().zip(b.as_bytes().iter()).zip(c.as_bytes().iter())
        .map(|((a,b),c)| {
            let a = (a-'0' as u8) as i32;
            let b = (b-'0' as u8) as i32;
            let c = (c-'0' as u8) as i32;
            
            if (a+b)%10 == c {
                (0,(a+b)/10)
            } else if (a+b+1)%10 == c {
                (1,(a+b)/10)
            } else {
                (2, (a+b)/10)
            }
        }).collect::<Vec<_>>();
    
    let mut is_valid_mid = vec![0; a.len()];
    let n = a.len();
    for i in 0..n {
        let carry = if i == n-1 {
            1
        } else {
            v[i+1].1
        };
        if v[i].0 <= 1 && v[i].0 == carry {
            is_valid_mid[i] = 1;
        }
    }

    // eprintln!("{v:?}");
    // eprintln!("{is_valid_mid:?}");

    let mut cnt_valid_no_carry = 0i64;
    let mut sum = 0i64;
    for i in 0..n {
        if v[i].0 == 0 {
            // eprintln!("{i}, {}", cnt_valid_no_carry);
            sum += cnt_valid_no_carry;
            if v[i].1 == 0 {
                sum += 1;
            }
        }
        if is_valid_mid[i] == 1 {
            if v[i].1 == 0 {
                cnt_valid_no_carry += 1;
            }
        } else {
            cnt_valid_no_carry = 0;
        }
    }
    println!("{sum}");
}