水题。
1 #include <cstdio> 2 #include <cstring> 3 #include <cstdlib> 4 5 int abs(int x) { 6 return x<0 ? -x:x; 7 } 8 9 int main() { 10 int t, n; 11 int cur, past; 12 __int64 ans; 13 bool flag; 14 15 #ifndef ONLINE_JUDGE 16 freopen("data.in", "r", stdin); 17 #endif 18 19 scanf("%d", &t); 20 for (int i=1; i<=t; ++i) { 21 scanf("%d", &n); 22 flag = true; 23 past = 0; 24 ans = 1; 25 while (n--) { 26 scanf("%d", &cur); 27 if (!flag) 28 continue; 29 if (abs(cur-past)>3 || (cur==past && cur!=1)) { 30 flag = false; 31 continue; 32 } 33 if (past == 0) 34 ans *= 2; 35 if (cur == 0) 36 ans /= 2; 37 if ((cur==1 && past==2) || (cur==2 && past==1)) 38 ans += 2; 39 past = cur; 40 } 41 if (!flag) 42 printf("Case #%d: 0 ", i); 43 else 44 printf("Case #%d: %I64d ", i, ans); 45 } 46 47 return 0; 48 }