package contest201113; import java.io.*; import java.util.*; public class D { InputStream is; FastWriter out; String INPUT = ""; static long I = 1000000000L; public void solve() { int n = ni(); char[] s = ns(n); int[] vs = na(n); List es = new ArrayList<>(); int sink = 4*n, src = 0; for(int i = 0;i < n;i++){ for(int j = 0;j < 4;j++){ if(i < n-1)es.add(new Edge(i+j*n, i+1+j*n, 5000, 0)); } int ind = "yuki".indexOf(s[i]); if(ind == -1)continue; es.add(new Edge(i+ind*n, ind < 3 ? i+(ind+1)*n : sink, 1, I-vs[i])); } long res = solveMinCostFlow(compileWD(sink+1, es), src, sink, 5000); // long[] res = solveMinCostFlowWithSPFA(compileWD(sink+1, es), src, sink, 2000); out.println(res); } public static class Edge { public int from, to; public long capacity; public long cost; public long flow; public Edge complement; // public int iniflow; public Edge(int from, int to, long capacity, long cost) { this.from = from; this.to = to; this.capacity = capacity; this.cost = cost; } @Override public String toString() { return "Edge [from=" + from + ", to=" + to + ", capacity=" + capacity + ", cost=" + cost + "]"; } } public static Edge[][] compileWD(int n, List edges) { Edge[][] g = new Edge[n][]; // cloning for(int i = edges.size()-1;i >= 0;i--){ Edge origin = edges.get(i); Edge clone = new Edge(origin.to, origin.from, origin.capacity, -origin.cost); clone.flow = origin.capacity; clone.complement = origin; origin.complement = clone; edges.add(clone); } int[] p = new int[n]; for(Edge e : edges)p[e.from]++; for(int i = 0;i < n;i++)g[i] = new Edge[p[i]]; for(Edge e : edges)g[e.from][--p[e.from]] = e; return g; } public static class DQ { public int[] q; public int n; protected int pt, ph; public DQ(int n){ this.n = Integer.highestOneBit(n)<<1; q = new int[this.n]; pt = ph = 0; } public void addLast(int x){ q[ph] = x; ph = ph+1&n-1; } public void addFirst(int x){ pt = pt+n-1&n-1; q[pt] = x; } public int pollFirst(){ int ret = q[pt]; pt = pt+1&n-1; return ret; } public int pollLast(){ ph = ph+n-1&n-1; int ret = q[ph]; return ret; } public int getFirst(){ return q[pt]; } public int getFirst(int k){ return q[pt+k&n-1]; } public int getLast(){ return q[ph+n-1&n-1]; } public int getLast(int k){ return q[ph+n-k-1&n-1]; } public void clear(){ pt = ph = 0; } public int size(){ return ph-pt+n&n-1; } public boolean isEmpty(){ return ph==pt; } } public static long solveMinCostFlow(Edge[][] g, int source, int sink, long all) { int n = g.length; long mincost = 0; long[] potential = new long[n]; final long[] d = new long[n]; MinHeapL q = new MinHeapL(n); long ff = 0; long ret = 0; while(all > 0){ // shortest path src->sink Edge[] inedge = new Edge[n]; Arrays.fill(d, Long.MAX_VALUE / 4); d[source] = 0; q.add(source, 0); while(q.size() > 0){ int cur = q.argmin(); q.remove(cur); for(Edge ne : g[cur]){ if(ne.capacity - ne.flow > 0){ long nd = d[cur] + ne.cost + potential[cur] - potential[ne.to]; if(d[ne.to] > nd){ inedge[ne.to] = ne; d[ne.to] = nd; q.update(ne.to, nd); } } } } if(inedge[sink] == null)break; long minflow = all; long sumcost = 0; for(Edge e = inedge[sink];e != null;e = inedge[e.from]){ if(e.capacity - e.flow < minflow)minflow = e.capacity - e.flow; sumcost += e.cost; } mincost += minflow * sumcost; for(Edge e = inedge[sink];e != null;e = inedge[e.from]){ e.flow += minflow; e.complement.flow -= minflow; } ff += minflow; all -= minflow; ret = Math.max(ret, (long)ff*I*4-mincost); for(int i = 0;i < n;i++){ potential[i] += d[i]; } } return ret; } public static class MinHeapL { public long[] a; public int[] map; public int[] imap; public int n; public int pos; public static long INF = Long.MAX_VALUE/4; public MinHeapL(int m) { n = Integer.highestOneBit((m+1)<<1); a = new long[n]; map = new int[n]; imap = new int[n]; Arrays.fill(a, INF); Arrays.fill(map, -1); Arrays.fill(imap, -1); pos = 1; } public long add(int ind, long x) { int ret = imap[ind]; if(imap[ind] < 0){ a[pos] = x; map[pos] = ind; imap[ind] = pos; pos++; up(pos-1); } return ret != -1 ? a[ret] : x; } public long update(int ind, long x) { int ret = imap[ind]; if(imap[ind] < 0){ a[pos] = x; map[pos] = ind; imap[ind] = pos; pos++; up(pos-1); }else{ a[ret] = x; up(ret); down(ret); } return x; } public long remove(int ind) { if(pos == 1)return INF; if(imap[ind] == -1)return INF; pos--; int rem = imap[ind]; long ret = a[rem]; map[rem] = map[pos]; imap[map[pos]] = rem; imap[ind] = -1; a[rem] = a[pos]; a[pos] = INF; map[pos] = -1; up(rem); down(rem); return ret; } public long min() { return a[1]; } public int argmin() { return map[1]; } public int size() { return pos-1; } private void up(int cur) { for(int c = cur, p = c>>>1;p >= 1 && a[p] > a[c];c>>>=1, p>>>=1){ long d = a[p]; a[p] = a[c]; a[c] = d; int e = imap[map[p]]; imap[map[p]] = imap[map[c]]; imap[map[c]] = e; e = map[p]; map[p] = map[c]; map[c] = e; } } private void down(int cur) { for(int c = cur;2*c < pos;){ int b = a[2*c] < a[2*c+1] ? 2*c : 2*c+1; if(a[b] < a[c]){ long d = a[c]; a[c] = a[b]; a[b] = d; int e = imap[map[c]]; imap[map[c]] = imap[map[b]]; imap[map[b]] = e; e = map[c]; map[c] = map[b]; map[b] = e; c = b; }else{ break; } } } } // negative is OK. public static long[] solveMinCostFlowWithSPFA(Edge[][] g, int source, int sink, long all) { int n = g.length; long mincost = 0; final long[] d = new long[n]; DQ q = new DQ(n); boolean[] inq = new boolean[n]; long ff = 0; while(all > 0){ // shortest path src->sink Edge[] inedge = new Edge[n]; Arrays.fill(d, Long.MAX_VALUE / 2); d[source] = 0; q.addLast(source); while(!q.isEmpty()){ int cur = q.pollFirst(); inq[cur] = false; for(Edge ne : g[cur]){ if(ne.capacity - ne.flow > 0){ long nd = d[cur] + ne.cost; if(d[ne.to] > nd){ inedge[ne.to] = ne; d[ne.to] = nd; if(!inq[ne.to]){ q.addLast(ne.to); inq[ne.to] = true; } } } } } if(inedge[sink] == null)break; long minflow = all; long sumcost = 0; for(Edge e = inedge[sink];e != null;e = inedge[e.from]){ if(e.capacity - e.flow < minflow)minflow = e.capacity - e.flow; sumcost += e.cost; } mincost += minflow * sumcost; for(Edge e = inedge[sink];e != null;e = inedge[e.from]){ e.flow += minflow; e.complement.flow -= minflow; } all -= minflow; ff += minflow; } return new long[]{ff, mincost}; } // neagtive is OK, and simple but maybe slower. public static long solveMinCostFlowWithBellmanFord(Edge[][] g, int source, int sink, long all) { int n = g.length; long mincost = 0; final long[] d = new long[n]; while(all > 0){ // shortest path src->sink Edge[] inedge = new Edge[n]; Arrays.fill(d, Long.MAX_VALUE / 2); d[source] = 0; int nease = 0; for(;;nease++){ boolean changed = false; for(Edge[] row : g){ for(Edge e : row){ if(e.capacity - e.flow > 0){ long nd = d[e.from] + e.cost; if(nd < d[e.to]){ d[e.to] = nd; inedge[e.to] = e; changed = true; } } } } if(!changed)break; if(nease == n-1){ // there are negative circuits. throw new RuntimeException(); } } if(inedge[sink] == null)break; long minflow = all; long sumcost = 0; boolean fromSource = false; for(Edge e = inedge[sink];e != null;e = inedge[e.from]){ if(e.capacity - e.flow < minflow)minflow = e.capacity - e.flow; sumcost += e.cost; if(e.from == source)fromSource = true; } if(!fromSource)break; mincost += minflow * sumcost; for(Edge e = inedge[sink];e != null;e = inedge[e.from]){ e.flow += minflow; e.complement.flow -= minflow; } all -= minflow; } return mincost; } public static void main(String[] args) { new D().run(); } public void run() { // int n = 996, m = 99999; // Random gen = new Random(); // StringBuilder sb = new StringBuilder(); // sb.append(n + "\n"); // for (int i = 0; i < n/4; i++) sb.append("yuk"); // for (int i = 0; i < n/4; i++) sb.append("i"); //// for (int i = 0; i < n/4; i++) sb.append("u"); //// for (int i = 0; i < n/4; i++) sb.append("k"); //// for (int i = 0; i < n/4; i++) sb.append("i"); // sb.append("\n"); // for(int i = 0;i < n;i++){ // sb.append(i+1 + " "); // } // INPUT = sb.toString(); long S = System.currentTimeMillis(); is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes()); out = new FastWriter(System.out); solve(); out.flush(); long G = System.currentTimeMillis(); tr(G-S+"ms"); // Thread t = new Thread(null, null, "~", Runtime.getRuntime().maxMemory()){ // @Override // public void run() { // long s = System.currentTimeMillis(); // solve(); // out.flush(); // if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms"); // } // }; // t.start(); // t.join(); } private boolean eof() { if(lenbuf == -1)return true; int lptr = ptrbuf; while(lptr < lenbuf)if(!isSpaceChar(inbuf[lptr++]))return false; try { is.mark(1000); while(true){ int b = is.read(); if(b == -1){ is.reset(); return true; }else if(!isSpaceChar(b)){ is.reset(); return false; } } } catch (IOException e) { return true; } } private final byte[] inbuf = new byte[1024]; public int lenbuf = 0, ptrbuf = 0; private int readByte() { if(lenbuf == -1)throw new InputMismatchException(); if(ptrbuf >= lenbuf){ ptrbuf = 0; try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); } if(lenbuf <= 0)return -1; } return inbuf[ptrbuf++]; } private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); } // private boolean isSpaceChar(int c) { return !(c >= 32 && c <= 126); } private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; } private double nd() { return Double.parseDouble(ns()); } private char nc() { return (char)skip(); } private String ns() { int b = skip(); StringBuilder sb = new StringBuilder(); while(!(isSpaceChar(b))){ sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } private char[] ns(int n) { char[] buf = new char[n]; int b = skip(), p = 0; while(p < n && !(isSpaceChar(b))){ buf[p++] = (char)b; b = readByte(); } return n == p ? buf : Arrays.copyOf(buf, p); } private char[][] nm(int n, int m) { char[][] map = new char[n][]; for(int i = 0;i < n;i++)map[i] = ns(m); return map; } private int[] na(int n) { int[] a = new int[n]; for(int i = 0;i < n;i++)a[i] = ni(); return a; } private long[] nal(int n) { long[] a = new long[n]; for(int i = 0;i < n;i++)a[i] = nl(); return a; } private int ni() { int num = 0, b; boolean minus = false; while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')); if(b == '-'){ minus = true; b = readByte(); } while(true){ if(b >= '0' && b <= '9'){ num = num * 10 + (b - '0'); }else{ return minus ? -num : num; } b = readByte(); } } private long nl() { long num = 0; int b; boolean minus = false; while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')); if(b == '-'){ minus = true; b = readByte(); } while(true){ if(b >= '0' && b <= '9'){ num = num * 10 + (b - '0'); }else{ return minus ? -num : num; } b = readByte(); } } public static class FastWriter { private static final int BUF_SIZE = 1<<13; private final byte[] buf = new byte[BUF_SIZE]; private final OutputStream out; private int ptr = 0; private FastWriter(){out = null;} public FastWriter(OutputStream os) { this.out = os; } public FastWriter(String path) { try { this.out = new FileOutputStream(path); } catch (FileNotFoundException e) { throw new RuntimeException("FastWriter"); } } public FastWriter write(byte b) { buf[ptr++] = b; if(ptr == BUF_SIZE)innerflush(); return this; } public FastWriter write(char c) { return write((byte)c); } public FastWriter write(char[] s) { for(char c : s){ buf[ptr++] = (byte)c; if(ptr == BUF_SIZE)innerflush(); } return this; } public FastWriter write(String s) { s.chars().forEach(c -> { buf[ptr++] = (byte)c; if(ptr == BUF_SIZE)innerflush(); }); return this; } private static int countDigits(int l) { if (l >= 1000000000) return 10; if (l >= 100000000) return 9; if (l >= 10000000) return 8; if (l >= 1000000) return 7; if (l >= 100000) return 6; if (l >= 10000) return 5; if (l >= 1000) return 4; if (l >= 100) return 3; if (l >= 10) return 2; return 1; } public FastWriter write(int x) { if(x == Integer.MIN_VALUE){ return write((long)x); } if(ptr + 12 >= BUF_SIZE)innerflush(); if(x < 0){ write((byte)'-'); x = -x; } int d = countDigits(x); for(int i = ptr + d - 1;i >= ptr;i--){ buf[i] = (byte)('0'+x%10); x /= 10; } ptr += d; return this; } private static int countDigits(long l) { if (l >= 1000000000000000000L) return 19; if (l >= 100000000000000000L) return 18; if (l >= 10000000000000000L) return 17; if (l >= 1000000000000000L) return 16; if (l >= 100000000000000L) return 15; if (l >= 10000000000000L) return 14; if (l >= 1000000000000L) return 13; if (l >= 100000000000L) return 12; if (l >= 10000000000L) return 11; if (l >= 1000000000L) return 10; if (l >= 100000000L) return 9; if (l >= 10000000L) return 8; if (l >= 1000000L) return 7; if (l >= 100000L) return 6; if (l >= 10000L) return 5; if (l >= 1000L) return 4; if (l >= 100L) return 3; if (l >= 10L) return 2; return 1; } public FastWriter write(long x) { if(x == Long.MIN_VALUE){ return write("" + x); } if(ptr + 21 >= BUF_SIZE)innerflush(); if(x < 0){ write((byte)'-'); x = -x; } int d = countDigits(x); for(int i = ptr + d - 1;i >= ptr;i--){ buf[i] = (byte)('0'+x%10); x /= 10; } ptr += d; return this; } public FastWriter write(double x, int precision) { if(x < 0){ write('-'); x = -x; } x += Math.pow(10, -precision)/2; // if(x < 0){ x = 0; } write((long)x).write("."); x -= (long)x; for(int i = 0;i < precision;i++){ x *= 10; write((char)('0'+(int)x)); x -= (int)x; } return this; } public FastWriter writeln(char c){ return write(c).writeln(); } public FastWriter writeln(int x){ return write(x).writeln(); } public FastWriter writeln(long x){ return write(x).writeln(); } public FastWriter writeln(double x, int precision){ return write(x, precision).writeln(); } public FastWriter write(int... xs) { boolean first = true; for(int x : xs) { if (!first) write(' '); first = false; write(x); } return this; } public FastWriter write(long... xs) { boolean first = true; for(long x : xs) { if (!first) write(' '); first = false; write(x); } return this; } public FastWriter writeln() { return write((byte)'\n'); } public FastWriter writeln(int... xs) { return write(xs).writeln(); } public FastWriter writeln(long... xs) { return write(xs).writeln(); } public FastWriter writeln(char[] line) { return write(line).writeln(); } public FastWriter writeln(char[]... map) { for(char[] line : map)write(line).writeln(); return this; } public FastWriter writeln(String s) { return write(s).writeln(); } private void innerflush() { try { out.write(buf, 0, ptr); ptr = 0; } catch (IOException e) { throw new RuntimeException("innerflush"); } } public void flush() { innerflush(); try { out.flush(); } catch (IOException e) { throw new RuntimeException("flush"); } } public FastWriter print(byte b) { return write(b); } public FastWriter print(char c) { return write(c); } public FastWriter print(char[] s) { return write(s); } public FastWriter print(String s) { return write(s); } public FastWriter print(int x) { return write(x); } public FastWriter print(long x) { return write(x); } public FastWriter print(double x, int precision) { return write(x, precision); } public FastWriter println(char c){ return writeln(c); } public FastWriter println(int x){ return writeln(x); } public FastWriter println(long x){ return writeln(x); } public FastWriter println(double x, int precision){ return writeln(x, precision); } public FastWriter print(int... xs) { return write(xs); } public FastWriter print(long... xs) { return write(xs); } public FastWriter println(int... xs) { return writeln(xs); } public FastWriter println(long... xs) { return writeln(xs); } public FastWriter println(char[] line) { return writeln(line); } public FastWriter println(char[]... map) { return writeln(map); } public FastWriter println(String s) { return writeln(s); } public FastWriter println() { return writeln(); } } public static void trnz(int... o) { for(int i = 0;i < o.length;i++)if(o[i] != 0)System.out.print(i+":"+o[i]+" "); System.out.println(); } // print ids which are 1 public static void trt(long... o) { Queue stands = new ArrayDeque<>(); for(int i = 0;i < o.length;i++){ for(long x = o[i];x != 0;x &= x-1)stands.add(i<<6|Long.numberOfTrailingZeros(x)); } System.out.println(stands); } public static void tf(boolean... r) { for(boolean x : r)System.out.print(x?'#':'.'); System.out.println(); } public static void tf(boolean[]... b) { for(boolean[] r : b) { for(boolean x : r)System.out.print(x?'#':'.'); System.out.println(); } System.out.println(); } public void tf(long[]... b) { if(INPUT.length() != 0) { for (long[] r : b) { for (long x : r) { for (int i = 0; i < 64; i++) { System.out.print(x << ~i < 0 ? '#' : '.'); } } System.out.println(); } System.out.println(); } } public void tf(long... b) { if(INPUT.length() != 0) { for (long x : b) { for (int i = 0; i < 64; i++) { System.out.print(x << ~i < 0 ? '#' : '.'); } } System.out.println(); } } private void tr(Object... o) { if(INPUT.length() != 0)System.out.println(Arrays.deepToString(o)); } }