import java.io.IOException; import java.io.InputStream; import java.util.Arrays; import java.util.NoSuchElementException; import java.util.PriorityQueue; class Main { public static void main(String[] args) { new Main().run(); } void run() { Scanner sc = new Scanner(); int N = sc.nextInt(); long[] C = new long[N]; long[] D = new long[N]; long ans = 0; for (int i = 0; i < N; ++i) { C[i] = sc.nextLong(); D[i] = sc.nextLong(); ans += C[i] + D[i]; } class Pair implements Comparable { long v; long min; public Pair(long v, long min) { this.v = v; this.min = min; } @Override public int compareTo(Pair o) { return Long.compare(min, o.min); } } PriorityQueue pq = new PriorityQueue<>(); long pending = -Long.MAX_VALUE / 3; for (int i = 0; i < N; ++i) { pq.add(new Pair(D[i] + (i == 0 ? 0 : pending), C[i])); pending = Math.max(pending, D[i] - C[i] + (i == 0 ? 0 : pending)); long max = -Long.MAX_VALUE / 3; while (!pq.isEmpty() && pq.peek().min >= C[i]) { Pair p = pq.poll(); max = Math.max(max, p.v); pending = Math.max(max - C[i], pending); } if (max != -Long.MAX_VALUE / 3) pq.add(new Pair(max, C[i])); } System.out.println(ans - pending); } void tr(Object... objects) { System.out.println(Arrays.deepToString(objects)); } } class Scanner { 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; } private void skipUnprintable() { while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; } public boolean hasNext() { skipUnprintable(); 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 int nextInt() { return (int) nextLong(); } 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(); } } }