package contest; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.Arrays; import java.util.InputMismatchException; public class Q622 { InputStream is; PrintWriter out; String INPUT = ""; void solve() { char[] s = ns().toCharArray(); int[][][][] pre = new int[21][21][21][21]; int[][][][] cur = new int[21][21][21][21]; for(int i = 0;i < 21;i++){ for(int j = 0;j < 21;j++){ for(int k = 0;k < 21;k++){ for(int l = 0;l < 21;l++){ pre[i][j][k][l] = -999999; } } } } pre[0][0][0][0] = 0; for(char c : s){ for(int i = 0;i < 21;i++){ for(int j = 0;j < 21;j++){ for(int k = 0;k < 21;k++){ for(int l = 0;l < 21;l++){ cur[i][j][k][l] = -999999; } } } } for(int i = 0;i < 21;i++){ for(int j = 0;j < 21;j++){ for(int k = 0;k < 21;k++){ for(int l = 0;l < 21;l++){ if(c == 'K' || c == '?'){ int ni = Math.min(i+1, 20); cur[ni][j][k][l] = Math.max(cur[ni][j][k][l], pre[i][j][k][l]); } if((c == 'U' || c == '?') && i >= 1){ int nj = Math.min(j+1, 20); cur[i-1][nj][k][l] = Math.max(cur[i-1][nj][k][l], pre[i][j][k][l]); } if((c == 'R' || c == '?') && j >= 1){ int nk = Math.min(k+1, 20); cur[i][j-1][nk][l] = Math.max(cur[i][j-1][nk][l], pre[i][j][k][l]); } if((c == 'O' || c == '?') && k >= 1){ int nl = Math.min(l+1, 20); cur[i][j][k-1][nl] = Math.max(cur[i][j][k-1][nl], pre[i][j][k][l]); } if((c == 'I' || c == '?') && l >= 1){ cur[i][j][k][l-1] = Math.max(cur[i][j][k][l-1], pre[i][j][k][l] + 1); } cur[i][j][k][l] = Math.max(cur[i][j][k][l], pre[i][j][k][l]); } } } } int[][][][] dum = pre; pre = cur; cur = dum; } int max = 0; for(int i = 0;i < 21;i++){ for(int j = 0;j < 21;j++){ for(int k = 0;k < 21;k++){ for(int l = 0;l < 21;l++){ max = Math.max(max, pre[i][j][k][l]); } } } } out.println(max); } void run() throws Exception { is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes()); out = new PrintWriter(System.out); long s = System.currentTimeMillis(); solve(); out.flush(); if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms"); } public static void main(String[] args) throws Exception { new Q622().run(); } private byte[] inbuf = new byte[1024]; private 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 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))){ // when nextLine, (isSpaceChar(b) && 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 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(); } } private static void tr(Object... o) { System.out.println(Arrays.deepToString(o)); } }