Algorithm

D. Quantity of Strings
time limit per test
2 seconds
memory limit per test
256 megabytes
Problem link- https://codeforces.com/contest/151/problem/D
input
standard input
output
standard output

Just in case somebody missed it: this winter is totally cold in Nvodsk! It is so cold that one gets funny thoughts. For example, let's say there are strings with the length exactly n, based on the alphabet of size m. Any its substring with length equal to k is a palindrome. How many such strings exist? Your task is to find their quantity modulo 1000000007 (109 + 7). Be careful and don't miss a string or two!

Let us remind you that a string is a palindrome if it can be read the same way in either direction, from the left to the right and from the right to the left.

Input

The first and only line contains three integers: n, m and k (1 ≤ n, m, k ≤ 2000).

Output

Print a single integer — the number of strings of the described type modulo 1000000007 (109 + 7).

Examples
input
Copy
1 1 1
output
Copy
1
input
Copy
5 2 4
output
Copy
2
Note

In the first sample only one string is valid: "a" (let's denote the only letter of our alphabet as "a").

In the second sample (if we denote the alphabet letters as "a" and "b") the following strings are valid: "aaaaa" and "bbbbb".



 

Code Examples

#1 Code Example with C++ Programming

Code - C++ Programming

#include <bits/stdc++.h>

using namespace std;

int const M = 1e9 + 7;

int main() {
  int n, m, k;
  scanf("%d %d %d", &n, &m, &k);

  long long res;

  if(n == k) {
    res = 1;
    for(int i = 0; i < (n + 1) / 2; ++i)
      res *= m,
      res %= M;
  } else if(k > n || k == 1) {
    res = 1;
    for(int i = 0; i < n; ++i)
      res *= m,
      res %= M;
  } else if(k % 2 == 0)
    res = m;
  else
    res = m * m;

  printf("%lld\n", res);

  return 0;
}
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Input

x
–
+
cmd
1 1 1

Output

x
–
+
cmd
1
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Demonstration

Codeforcess Solution Quantity of Strings, D. Quantity of Strings ,C,C++, Java, Js and Python ,Quantity of Strings,Codeforcess Solution

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