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// 1617. Bit Strings
#include <bits/stdc++.h>
const int mod = 1e9 + 7;
long long fast_pow2(int x) {
long long res = 1, y = 2;
while (x) {
if (x & 1)
res = (res * y) % mod;
y = (y * y) % mod;
x >>= 1;
}
return res;
}
int main() {
static int n;
scanf("%d", &n);
printf("%lld\n", fast_pow2(n));
}
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