๋ฐฑ์ค 10844๋ฒ
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const fs = require('fs');
const input = +fs.readFileSync('/dev/stdin').toString().trim();
let dp = Array.from(new Array(input + 1), () => new Array(10));
dp[1] = [0, 1, 1, 1, 1, 1, 1, 1, 1, 1];
dp[2] = [1, 1, 2, 2, 2, 2, 2, 2, 2, 1];
for (let n = 3; n <= input; n++) {
for (let i = 0; i < 10; i++) {
if (i === 0) {
dp[n][i] = dp[n - 1][i + 1] % 1000000000;
} else if (i === 9) {
dp[n][i] = dp[n - 1][i - 1] % 1000000000;
} else {
dp[n][i] = (dp[n - 1][i - 1] + dp[n - 1][i + 1]) % 1000000000;
}
}
}
const result = dp[input].reduce((a, b) => a + b, 0);
console.log(result % 1000000000);