#include <bits/stdc++.h>
#define pb push_back
#define s second
#define f first
#define ll long long
#define int ll
using namespace std;
string str;
int dp[15][15][25][5];
int get(int last2,int last,int len,int sm){
if (len >= str.size()) return 1;
if (dp[last2][last][len][sm] != -1)
return dp[last2][last][len][sm];
if (sm){
for (int i = 0; i <= 9; i++){
if (i != last && i != last2)
sum += get(last,i,len + 1,1);
}
}
else{
int l = str[len] - '0',sum = 0;
for (int i = 0; i < l; i++){
if (i != last && i != last2)
sum += get(last,i,len + 1,1);
}
if (l != last && l != last2)
sum += get(last,l,len + 1,0);
}
return dp[last2][last][len][sm] = sum;
}
int G(int x){
if (x < 0) return 0;
memset(dp, -1, sizeof(dp));
str = "";
while(x > 0){
str+=char((x%10)+'0');
x/=10;
}
reverse(str.begin(),str.end());
int l = str[0] - '0',ans = 1;
for (int i = 1; i < l; i++)
ans += get(i,i,1,1);
ans += get(l,l,1,0);
for (int i = 2; i <= str.size(); i++)
for (int j=1;j<=9;j++)
ans += get(j,j,i,1);
return ans;
}
signed main (){
ios_base::sync_with_stdio(0),cin.tie(NULL),cout.tie(NULL);
ll a,b;
cin>>a>>b;
cout<<G(b) - G(a - 1)<<"\n";
}
Compilation message
numbers.cpp: In function 'long long int get(long long int, long long int, long long int, long long int)':
numbers.cpp:13:13: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
13 | if (len >= str.size()) return 1;
| ~~~~^~~~~~~~~~~~~
numbers.cpp:20:17: error: 'sum' was not declared in this scope; did you mean 'sm'?
20 | sum += get(last,i,len + 1,1);
| ^~~
| sm
numbers.cpp:33:39: error: 'sum' was not declared in this scope; did you mean 'sm'?
33 | return dp[last2][last][len][sm] = sum;
| ^~~
| sm
numbers.cpp: In function 'long long int G(long long int)':
numbers.cpp:50:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
50 | for (int i = 2; i <= str.size(); i++)
| ~~^~~~~~~~~~~~~
