omo省选前夜… I'm Crawling Back to U...
若干坑点:
solve(x)是指小于x的windy数数量… 所以答案应是solve(b+1) - solve(a)
还有数组大小问题… B了狗了…
// BZOJ 1026 数位DP
#include <cstdio>
#include <cstring>
#include <cstdlib>
using namespace std;
#define read(x) scanf("%lld", &x)
#define rep(i,a,b) for (int i = a; i <= b; i++)
#define dep(i,a,b) for (int i = a; i >= b; i--)
#define LL long long
const int Len = 10;
int d[Len+2][12], bit[Len+2];
void init() {
memset(d, 0, sizeof(d));
rep(i, 0, 9) d[1][i] = 1;
rep(i, 2, Len)
rep(j, 0, 9)
rep(k, 0, 9)
if (abs(j-k) >= 2) d[i][j] += d[i-1][k];
}
int solve(LL x) { // x = abcd
int cnt = 0, ret = 0;
if (x <= 2) return 0;
else if (x <= 9) return x-2;
while (x > 0) {
bit[++cnt] = x%10;
x /= 10;
}
dep(i, bit[cnt]-1, 1) ret += d[cnt][i]; // 1xxx~3xxx (x<当前位数字)
dep(i, cnt-1, 1) // 0xxx
rep(j, 1, 9)
ret += d[i][j];
dep(i, cnt-1, 1) { // axxx, abxx, abcx
rep(j, 0, bit[i]-1)
if (abs(bit[i+1]-j) >= 2) ret += d[i][j];
if (abs(bit[i]-bit[i+1]) <= 1) break;
}
return ret;
}
int a, b;
int main()
{
read(a); read(b);
init();
printf("%d
", solve(b+1)-solve(a));
return 0;
}