#15. 牢不可破的子序列

https://sjzezoj.com/submission/21445

S2OJ/15/15.cpp

@@ -0,0 +1,24 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int n, k, a;
+long long sum[5000005], f[5000005], now = INT_MIN;
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin >> n >> k;
+    for (int i = 1; i <= n; ++i) {
+        cin >> a;
+        sum[i] = sum[i - 1] + a;
+    }
+    for (int i = 1; i <= n; ++i) {
+        f[i] = f[i - 1];
+        if (i - k >= 0) {
+            now = max(now, f[i - k] - sum[i - k]);
+            f[i] = max(f[i], now + sum[i]);
+        }
+    }
+    cout << f[n] << endl;
+    return 0;
+}