///usr/bin/g++ -O2 $0 -o ${0%.cpp} && echo "----------" && ./${0%.cpp}; exit; #include <bits/stdc++.h> using namespace std; typedef long long ll; typedef pair<int, int> ii; const int N = 50; int n; ll X; vector<ll> a, b; void gen(int i, vector<ll> &a, vector<ll> &A, ll S = 0) { if(S > X) return; if(i == a.size()) { A.push_back(S); return; } gen(i + 1, a, A, S + a[i]); gen(i + 1, a, A, S); } int main() { scanf("%d %lld", &n, &X); vector<ll> a, b; for(int i = 0; i < n; i++) { ll x; scanf("%lld", &x); if(i < n / 2) a.push_back(x); else b.push_back(x); } vector<ll> A, B; gen(0, a, A); gen(0, b, B); sort(A.begin(), A.end()); ll ans = 0; for(ll Y : B) ans += lower_bound(A.begin(), A.end(), X - Y + 1) - A.begin(); printf("%lld\n", ans); }

bobek.cpp: In function 'void gen(int, std::vector<long long int>&, std::vector<long long int>&, ll)':
bobek.cpp:14:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if(i == a.size()) { A.push_back(S); return; }
        ~~^~~~~~~~~~~
bobek.cpp: In function 'int main()':
bobek.cpp:20:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %lld", &n, &X);
     ~~~~~^~~~~~~~~~~~~~~~~~~
bobek.cpp:23:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         ll x; scanf("%lld", &x); 
               ~~~~~^~~~~~~~~~~~