H - F(x)
1 #include <iostream> 2 #include <algorithm> 3 #include <cstring> 4 #include <cstdio> 5 #include <string> 6 using namespace std; 7 typedef long long ll; 8 9 const int maxn = 1e4+5; 10 int dp[15][maxn]; //pos sum 11 int Max; 12 int aa[15]; 13 14 int f(int x){ 15 int ans = 0; 16 int cnt = 1; 17 while(x){ 18 ans = ans + x%10*cnt; 19 x /= 10; 20 cnt *= 2; 21 } 22 return ans; 23 } 24 25 int dfs(int pos, int sum, bool limit){ 26 if(pos == -1) return sum <= Max; //是否满足条件 27 if(sum > Max) return 0; 28 if(!limit && dp[pos][Max - sum] != -1) 29 return dp[pos][Max - sum]; 30 int up = limit?aa[pos]:9; 31 int ans = 0; 32 for(int i = 0; i <= up;i++){ 33 ans += dfs(pos-1, sum+ i*(1<<pos), limit&&i == aa[pos]); 34 } 35 if(!limit) dp[pos][Max - sum] = ans; 36 return ans; 37 } 38 39 int solve(int x){ 40 int pos = 0; 41 while(x){ 42 aa[pos++] = x%10; 43 x /= 10; 44 } 45 return dfs(pos-1, 0, true); //最高位是有限制的 46 } 47 48 int main(){ 49 memset(dp, -1, sizeof dp); 50 int t; 51 scanf("%d", &t); 52 int Case = 0; 53 while(t--){ 54 // memset(dp, -1, sizeof(dp)); 55 Case++; 56 int a, b; 57 scanf("%d%d", &a, &b); 58 Max = f(a); 59 int ans = solve(b); 60 printf("Case #%d: %d\n", Case, ans); 61 } 62 return 0; 63 }
