new file: P15791.cpp

P15791.cpp

@@ -0,0 +1,67 @@
+#include <bits/stdc++.h>
+int n, m;
+int a[500005];
+int t[500005];
+using namespace std;
+struct seg {
+    int l, r;
+    long long num, lz;
+} seg[2000005];
+void pd(int now) {
+    seg[now * 2].lz += seg[now].lz, seg[now * 2 + 1].lz += seg[now].lz;
+    seg[now * 2].num += seg[now].lz, seg[now * 2 + 1].num += seg[now].lz;
+    seg[now].lz = 0;
+}
+void pu(int now) { seg[now].num = max(seg[now * 2].num, seg[now * 2 + 1].num); }
+void init(int now, int l, int r) {
+    seg[now].l = l, seg[now].r = r;
+    if (l == r) {
+        return;
+    }
+    int mid = (l + r) >> 1;
+    init(now * 2, l, mid);
+    init(now * 2 + 1, mid + 1, r);
+}
+long long query(int now, int l, int r) {
+    if (r < seg[now].l || l > seg[now].r) {
+        return -1e18;
+    }
+    if (r >= seg[now].r && l <= seg[now].l) {
+        return seg[now].num;
+    }
+    pd(now);
+    return max(query(now * 2, l, r), query(now * 2 + 1, l, r));
+}
+void edit(int now, int l, int r, long long num) {
+    if (r < seg[now].l || l > seg[now].r) {
+        return;
+    }
+    if (r >= seg[now].r && l <= seg[now].l) {
+        seg[now].num += num, seg[now].lz += num;
+        return;
+    }
+    pd(now);
+    edit(now * 2, l, r, num);
+    edit(now * 2 + 1, l, r, num);
+    pu(now);
+}
+int pre[500005];
+int main() {
+    scanf("%d%d", &n, &m);
+    init(1, 1, n);
+    for (int i = 1; i <= n; ++i) {
+        scanf("%d", &a[i]);
+    }
+    for (int i = 1; i <= m; ++i) {
+        scanf("%d", &t[i]);
+    }
+    for (int i = 1; i <= n; ++i) {
+        if (pre[a[i]])
+            edit(1, pre[a[i]], i - 1, t[a[i]]);
+        pre[a[i]] = i;
+        if (i > 1)
+            edit(1, i, i, max(query(1, 1, i - 1), 0ll));
+    }
+    printf("%lld\n", query(1, 1, n));
+    return 0;
+}