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// 1220. Count Vowels Permutation
#include <stdio.h>
#include <stdlib.h>
int countVowelPermutation(int n) {
int mod = 1e9 + 7, ans = 0;
long long int dp[n + 1][5];
for (int i = 0; i < 5; i++)
dp[1][i] = 1;
for (int i = 2; i < n + 1; i++) {
dp[i][0] = (dp[i - 1][1] + dp[i - 1][2] + dp[i - 1][4]) % mod;
dp[i][1] = (dp[i - 1][0] + dp[i - 1][2]) % mod;
dp[i][2] = (dp[i - 1][1] + dp[i - 1][3]) % mod;
dp[i][3] = dp[i - 1][2];
dp[i][4] = (dp[i - 1][2] + dp[i - 1][3]) % mod;
}
for (int i = 0; i < 5; i++)
ans = (ans + dp[n][i]) % mod;
return ans;
}
int main() {
printf("%d\n", countVowelPermutation(1)); // expect: 5
printf("%d\n", countVowelPermutation(2)); // expect: 10
printf("%d\n", countVowelPermutation(5)); // expect: 68
}
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