Editorial
The formula of the binomial theorem is as follows:
If we set , then this relation takes the following form:
or
Thus, the indicated sum equals .
Example
If , then
If , then
If , then
Algorithm realization
Read the input value of .
scanf("%lld", &n);
Compute and print the result, the value of .
res = 1LL << n; printf("%lld\n", res);
Python realization
Read the input value of .
n = int(input())
Compute and print the result, the value of .
res = 1 << n print(res)