1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
#include <bits/stdc++.h>

using namespace std;
using ll = long long;

constexpr int N = 1e6 + 5;

int a[N], b[N], c[N], n, mul, rem;
string s1, s2, s3;
bool state;
ll ans = 0;

int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    cin >> s1 >> s2 >> s3;
    n = s1.size();
    for(int i = 0; i < n; ++i) a[i] = s1[i] - '0', b[i] = s2[i] - '0', c[i] = s3[i] - '0';
    mul = 0, ans = 0, state = 0, rem = 0;
    for(int i = n - 1; i >= 0; --i) {
        if(state) {
            if(a[i] + b[i] == c[i]) {
                mul = 1;
                rem = 0;
                state = 0;
                ans += mul;
            } else if ((a[i] + b[i]) % 10 == c[i]){
                mul = 0;
                rem = (a[i] + b[i]) / 10;
            } else if(a[i] + b[i] + rem == c[i]) {
                ++mul;
                state = 0;
                rem = 0;
                ans += mul;
            } else if((a[i] + b[i] + rem) % 10 == c[i]) {
                rem = (a[i] + b[i] + rem) / 10;
            } else {
                mul = 0;
                rem = 0;
                state = 0;
            }
        } else {
            if(a[i] + b[i] == c[i]) {
                mul++;
                ans += mul;
            } else if((a[i] + b[i]) % 10 == c[i]) {
                state = 1;
                rem = (a[i] + b[i]) / 10;
            } else {
                mul = 0;
            }
        }
    }
    cout << ans << '\n';
}