UVa12545 Bits Equalizer (贪心)

 1 #include <cstdio>
 2 #include <cstring>
 3 using namespace std;
 4 
 5 const int maxn = 100 + 5;
 6 
 7 char s[maxn], t[maxn];
 8 
 9 int main() {
10     int T;
11     scanf("%d", &T);
12     for (int kase = 1; kase <= T; kase++) {
13         scanf("%s%s", s, t);
14         int pr01 = 0, pr10 = 0, prq0 = 0, prq1 = 0;
15         for (int i = 0; i < strlen(s); i++) {
16             if (s[i] == ‘0‘ && t[i] == ‘1‘) pr01++;
17             if (s[i] == ‘1‘ && t[i] == ‘0‘) pr10++;
18             if (s[i] == ‘?‘ && t[i] == ‘0‘) prq0++;
19             if (s[i] == ‘?‘ && t[i] == ‘1‘) prq1++;
20         }
21         int ans = 0;
22         while (pr01 && pr10) {
23             pr01--; pr10--;
24             ans++;
25         }
26         while (pr10 && prq1) {
27             pr10--; prq1--;
28             ans += 2;
29         }
30         if (pr10) ans = -1;
31         else ans += pr01 + prq0 + prq1;
32         printf("Case %d: %d\n", kase, ans);
33     }
34     return 0;
35 }