new file: P2602.cpp

P2602.cpp

@@ -0,0 +1,48 @@
+#include <bits/stdc++.h>
+using namespace std;
+#define int long long
+
+int dig[20], len;
+int dp[20][20][2][2]; // pos, cnt, limm, fl
+int dfs(int pos, int cnt, bool limm, bool fl, int too)
+{
+    if (pos == len)
+        return cnt;
+    if (dp[pos][cnt][limm][fl] != -1)
+        return dp[pos][cnt][limm][fl];
+    int up = limm ? dig[pos] : 9;
+    int res = 0;
+    for (int d = 0; d <= up; ++d)
+    {
+        bool nl = fl && (d == 0);
+        int add = 0;
+        if (!(fl && d == 0) && d == too)
+            add = 1;
+        res += dfs(pos + 1, cnt + add, limm && (d == up), nl, too);
+    }
+    return dp[pos][cnt][limm][fl] = res;
+}
+int doo(int n, int too)
+{
+    if (n <= 0)
+        return 0;
+    len = 0;
+    while (n)
+    {
+        dig[len++] = n % 10;
+        n /= 10;
+    }
+    reverse(dig, dig + len);
+    memset(dp, -1, sizeof(dp));
+    return dfs(0, 0, true, true, too);
+}
+signed main()
+{
+    int a, b;
+    cin >> a >> b;
+    for (int i = 0; i <= 9; ++i)
+    {
+        cout << doo(b, i) - doo(a - 1, i) << ' ';
+    }
+    return 0;
+}