#include<bits/stdc++.h>
using namespace std;
long long val1;
long long powers10[20];
long long dp[20][11][11][2];
long long solveBasic(long long d, long long p1, long long p2, long long isroot){
if(d == -1){
return 1;
}
if(dp[d][p1][p2][isroot]){
return dp[d][p1][p2][isroot];
}
long long ans = 0;
for (long long i = 0; i < 10; i++) {
if(isroot && i == 0){
continue;
}
if(i != p1 && i != p2){
ans += solveBasic(d - 1, p2, i, 0);
}
}
return dp[d][p1][p2][isroot] = ans;
}
long long countLeqPow(long long d, long long p1, long long p2, long long isroot){
if(d == -1){
return 1;
}
long long ans = 0;
for (long long i = 0; i < 10; i++) {
if(isroot && i == 0){
continue;
}
if((val1 / powers10[d]) % 10 < i){
break;
}
if(i != p1 && i != p2){
if((val1 / powers10[d]) % 10 == i){
ans += countLeqPow(d - 1, p2, i, 0);
break;
}
else ans += solveBasic(d-1,p2,i,0);
}
}
return ans;
}
long long countLeq(long long x){
if(x == -1){
return 0;
}
val1 = x;
long long ans = 0;
long long i, bount = (long long)(lower_bound(powers10,powers10 + 19, x + 1) - powers10);
for (i=0; i<bount; i++) {
ans += solveBasic(i - 1, 10, 10, 1);
}
ans += countLeqPow(bount - 1, 10, 10, 1);
return ans;
}
long long main(){
long long a, b;
cin >> a >> b;
powers10[0] = 1;
for(long long i = 1; i < 19; i++){
powers10[i] = powers10[i-1] * 10;
}
cout << countLeq(b) - countLeq(a - 1) << "\n";
}
Compilation message
cc1plus: error: '::main' must return 'int'
