UPC5431/acm icpc 2017 Tehran Column Addition

 1 #include <bits/stdc++.h>
 2  
 3 const int maxn = 1007;
 4 int need[maxn], add[maxn], a[maxn], b[maxn], c[maxn], n;
 5 int f[maxn];
 6  
 7 void read(int *tmp) {
 8     for (int i = n; i >= 1; i--) {
 9         char tm;
10         scanf(" %c", &tm);
11         tmp[i] = tm - ‘0‘;
12     }
13 }
14  
15 int main() {
16 //    freopen("in.txt", "r", stdin);
17     while (scanf("%d", &n), n > 0) {
18         read(a), read(b), read(c);
19         int tot = n;
20         for (int i = 1; i <= n; i++) {
21             int tmp = a[i] + b[i];
22             if (tmp == 9 && c[i] == 0) need[i] = 1;
23             else need[i] = c[i] - tmp % 10;
24             add[i] = (tmp + need[i]) / 10;
25         }
26         while (add[n]) n--;
27         for (int i = 1; i <= n; ++i) {
28             f[i] = -0x3f3f3f3f;
29             if (need[i] == 0) f[i] = 1;
30             for (int j = i - 1; j >= 1; j--) {
31                 if (need[i] == add[j] && f[j] >= 0) f[i] = std::max(f[j] + 1, f[i]);
32             }
33         }
34         int ans = 0;
35         for (int i = 1; i <= n; i++) if(add[i] == 0) ans = std::max(ans, f[i]);
36         printf("%d\n", tot - ans);
37     }
38     return 0;
39 }