func_code_string: #include <bits/stdc++.h>   using namespace std;   const int mod = 998244353;   int power(int v, int u) {     if (!u) return 1;     int ok = power(v, u >> 1);     if (u & 1) return (long long)ok * ok % mod * v % mod;     return (long long)ok * ok % mod;   }   const int maxm = 2e5;   int b[maxm + 10];   int main() {     int n, m, A;     scanf( %d%d%d , &n, &m, &A);     for (int i = 1; i <= m; i++) scanf( %d , &b[i]);     int ans = 1;     int inv2 = power(2, mod - 2);     for (int i = 1; i <= m; i++)       ans = (long long)ans *             (((long long)power(A, 2 * (b[i] - b[i - 1])) +               power(A, b[i] - b[i - 1])) %              mod * inv2 % mod) %             mod;     ans = (long long)ans * power(A, n - b[m] - b[m]) % mod;     printf( %d n , ans);     return 0;   }   