import java.util.*; import java.io.*; public class Main { static ArrayList[] graph; public static void main(String[] args) throws Exception { FastScanner sc = new FastScanner(); int a = sc.nextInt(); int b = sc.nextInt(); int c = sc.nextInt(); int sum = b * 10 + a; int min = Integer.MAX_VALUE; for (int i = 0; i <= c; i++) { int ans = sum - (c - i) * 10 - i; int count = a; int mod = ans % 10; if (mod != 0) { count += 10 - mod; } if (ans > 0 && i <= count) { min = Math.min(ans, min); } } if (min == Integer.MAX_VALUE) { System.out.println("Impossible"); } else { System.out.println(min); } } static void search(int to, long[] costs, long value) { if (costs[to] <= value) { return; } costs[to] = value; for (Path p : graph[to]) { int next; if (p.from == to) { next = p.to; } else { next = p.from; } search(next, costs, value + p.cost); } } static class Path { int to; int from; int cost; public Path (int to, int from, int cost) { this.to = to; this.from = from; this.cost = cost; } } } class FastScanner { private final InputStream in = System.in; private final byte[] buffer = new byte[1024]; private int ptr = 0; private int buflen = 0; private boolean hasNextByte() { if (ptr < buflen) { return true; }else{ ptr = 0; try { buflen = in.read(buffer); } catch (IOException e) { e.printStackTrace(); } if (buflen <= 0) { return false; } } return true; } private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;} private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;} public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();} public String next() { if (!hasNext()) throw new NoSuchElementException(); StringBuilder sb = new StringBuilder(); int b = readByte(); while(isPrintableChar(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public long nextLong() { if (!hasNext()) throw new NoSuchElementException(); long n = 0; boolean minus = false; int b = readByte(); if (b == '-') { minus = true; b = readByte(); } if (b < '0' || '9' < b) { throw new NumberFormatException(); } while(true){ if ('0' <= b && b <= '9') { n *= 10; n += b - '0'; }else if(b == -1 || !isPrintableChar(b)){ return minus ? -n : n; }else{ throw new NumberFormatException(); } b = readByte(); } } public int nextInt() { long nl = nextLong(); if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException(); return (int) nl; } public double nextDouble() { return Double.parseDouble(next()); } }