add CWC201

cwc2015.cpp

@@ -0,0 +1,33 @@
+// 2015-11-04
+#include <iostream>
+#include <bitset>
+#include <vector>
+#include <cstdio>
+using namespace std;
+int main() {
+    int T;
+    cin >> T;
+    for (int _cs = 1; _cs <= T; _cs++) {
+        int N;
+        cin >> N;
+        int sum = 0;
+        vector<int> x(N);
+        for (int i = 0; i < N; i++) {
+            cin >> x[i];
+            sum += x[i];
+        }
+        printf("Case %d: ", _cs);
+        if (sum%2 || N%2) {
+            puts("No");
+            continue;
+        }
+        vector<bitset<41>> dp(sum+1);
+        dp[0][0] = 1;
+        for (int i = 0; i < N; i++) {
+            for (int j = dp.size() -1; j >= x[i]; j--) {
+                dp[j] |= dp[j-x[i]] << 1;
+            }
+        }
+        puts(dp[sum/2][N/2] ? "Yes" : "No");
+    }
+}