new file: P15256.cpp

P15256.cpp

@@ -0,0 +1,43 @@
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+
+int main() {
+    int N, Q;
+    scanf("%d %d", &N, &Q);
+    vector<ll> a(N + 1);
+    for (int i = 1; i <= N; ++i) {
+        scanf("%lld", &a[i]);
+    }
+    const int MAXI = 31;
+    vector<ll> dp(MAXI + 2, 0);
+    dp[1] = a[1];
+    for (int i = 2; i <= MAXI; ++i) {
+        if (i <= N)
+            dp[i] = min(a[i], 2 * dp[i - 1]);
+        else
+            dp[i] = 2 * dp[i - 1];
+    }
+
+    while (Q--) {
+        ll x;
+        scanf("%lld", &x);
+        ll ans = LLONG_MAX;
+        ll cur_cost = 0;
+        bool tight = true;
+        for (int i = 30; i >= 0; --i) {
+            if (tight) {
+                if ((x >> i) & 1LL) {
+                    cur_cost += dp[i + 1];
+                } else {
+                    ans = min(ans, cur_cost + dp[i + 1]);
+                }
+            } else {
+                break;
+            }
+        }
+        ans = min(ans, cur_cost);
+        printf("%lld\n", ans);
+    }
+    return 0;
+}