比windy数这道题要简单一点:
#include <cmath>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#define ll long long
#define rep(i,x,y) for(ll i=(x);i<=(y);i++)
#define repl(i,x,y) for(ll i=(x);i<(y);i++)
#define repd(i,x,y) for(ll i=(x);i>=(y);i--)
using namespace std;
const ll N=55;
const ll Inf=1e18;
ll x,y,w[N],f[N][N];
void split(ll x) {
w[0]=0;
while(x) {
w[++w[0]]=x%10;x/=10;
}w[w[0]+1]=0;
}
ll calc(ll x) {
ll ans=0;
split(x);
repd(i,w[0],1) {
if(w[i+1]>w[i]) break;
repl(j,w[i+1],w[i]) ans+=f[i][j];
if(i==1) ans++;
}
return ans;
}
int main() {
rep(i,1,9) f[1][i]=1;
repl(i,2,N) rep(j,0,9) rep(k,j,9) f[i][j]+=f[i-1][k];
while(~scanf("%lld%lld",&x,&y)) printf("%lld\n",calc(y)-calc(x-1));
return 0;
}