ACdream 完美数 数位DP
题目链接：http://www.acdream.net/problem.php?id=1083
简单数位DP，貌似我写得太暴力了= =
1 //STATUS:C++_AC_20MS_1512KB 2 #include<stdio.h> 3 #include<stdlib.h> 4 #include<string.h> 5 #include<math.h> 6 #include<iostream> 7 #include<string> 8 #include<algorithm> 9 #include<vector> 10 #include<queue> 11 #include<stack> 12 #include<map> 13 using namespace std; 14 #define LL __int64 15 #define pii pair<int,int> 16 #define Max(a,b) ((a)>(b)?(a):(b)) 17 #define Min(a,b) ((a)<(b)?(a):(b)) 18 #define mem(a,b) memset(a,b,sizeof(a)) 19 #define lson l,mid,rt<<1 20 #define rson mid+1,r,rt<<1|1 21 const int N=15,M=100000,INF=0x3f3f3f3f,MOD=100000000; 22 const double DNF=100000000000; 23 24 int a[N][11],b[N][11],d[N]; 25 int T,n,m; 26 27 int geta(int n) 28 { 29 int i,j,t,num[N],len=0,ret=0,ok=0; 30 do{num[len++]=n%10;} 31 while(n/=10); 32 for(i=len-1;i>=0;i--){ 33 for(j=0;j<num[i];j++)ret+=a[i][j]; 34 if(num[i]==8)break; 35 if(num[i]==3){ 36 for(t=1,i--;i>=0;i--){ 37 if(ok)num[i]=9; 38 if(num[i]==8)ok=1; 39 t+=(num[i]-(num[i]>=8?1:0))*d[i]; 40 } 41 ret+=t; 42 } 43 } 44 return ret; 45 } 46 47 int getb(int n) 48 { 49 int i,j,t,num[N],len=0,ret=0,ok=0; 50 do{num[len++]=n%10;} 51 while(n/=10); 52 for(i=len-1;i>=0;i--){ 53 for(j=0;j<num[i];j++)ret+=b[i][j]; 54 if(num[i]==3)break; 55 if(num[i]==8){ 56 for(t=1,i--;i>=0;i--){ 57 if(ok)num[i]=9; 58 if(num[i]==3)ok=1; 59 t+=(num[i]-(num[i]>=3?1:0))*d[i]; 60 } 61 ret+=t; 62 } 63 } 64 return ret; 65 } 66 67 int main() 68 { 69 // freopen("in.txt","r",stdin); 70 int i,j,k; 71 d[0]=1; 72 for(i=1;i<=9;i++)d[i]=d[i-1]*9; 73 a[0][3]=1,b[0][8]=1; 74 for(i=1;i<=9;i++){ 75 for(j=0;j<=9;j++){ 76 if(j==8)continue; 77 if(j!=3)for(k=0;k<=9;k++){ 78 if(k==8)continue; 79 a[i][j]+=a[i-1][k]; 80 } 81 else a[i][j]=d[i]; 82 } 83 } 84 for(i=1;i<=9;i++){ 85 for(j=0;j<=9;j++){ 86 if(j==3)continue; 87 if(j!=8)for(k=0;k<=9;k++){ 88 if(k==3)continue; 89 b[i][j]+=b[i-1][k]; 90 } 91 else b[i][j]=d[i]; 92 } 93 } 94 scanf("%d",&T); 95 while(T--) 96 { 97 scanf("%d%d",&n,&m); 98 n--; 99 printf("%d\n",geta(m)-geta(n)+getb(m)-getb(n)); 100 } 101 return 0; 102 }
