ソースコード
#include <cstdio>
#include <cassert>
#include <cmath>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <functional>
#include <stack>
#include <queue>
#include <tuple>
#define getchar getchar_unlocked
#define putchar putchar_unlocked
#define _rep(_1, _2, _3, _4, name, ...) name
#define rep2(i, n) rep3(i, 0, n)
#define rep3(i, a, b) rep4(i, a, b, 1)
#define rep4(i, a, b, c) for (int i = int(a); i < int(b); i += int(c))
#define rep(...) _rep(__VA_ARGS__, rep4, rep3, rep2, _)(__VA_ARGS__)
using namespace std;
using i64 = long long;
using u8 = unsigned char;
using u32 = unsigned;
using u64 = unsigned long long;
using f80 = long double;
int get_int() {
int c, n;
while ((c = getchar()) < '0');
n = c - '0';
while ((c = getchar()) >= '0') n = n * 10 + (c - '0');
return n;
}
void solve() {
int N, M;
while (~scanf("%d %d", &N, &M)) {
i64 s = 0;
rep(i, N) s += get_int();
printf("%llu\n", s * M);
}
}
int main() {
clock_t beg = clock();
solve();
clock_t end = clock();
fprintf(stderr, "%.3f sec\n", double(end - beg) / CLOCKS_PER_SEC);
return 0;
}