#include <cstdio>#include <iostream>#include <cstring>#include <algorithm>using namespace std;const int MAXN = 1010;struct Node { int l, r, pow, id; bool operator < (const Node &rhs) const { if(r != rhs.r) return r < rhs.r; return l < rhs.l; } bool operator == (const Node &rhs) const { return l == rhs.l && r == rhs.r; }};int n;Node a[MAXN];int dp[MAXN], pre[MAXN], last[MAXN];bool use[MAXN], ans[MAXN];void solve() { memset(dp, 0, sizeof(dp)); int cur = 0; for(int i = 1; i <= n; ++i) { pre[i] = i - 1; dp[i] = dp[i - 1]; last[i] = -1; while(cur < n && a[cur].r == i) { if(dp[i] < dp[a[cur].l - 1] + a[cur].pow) { pre[i] = a[cur].l - 1; dp[i] = dp[a[cur].l - 1] + a[cur].pow; last[i] = cur; } ++cur; } }}void output() { int cur = n; while(cur > 0) { if(last[cur] != -1) use[last[cur]] = true; cur = pre[cur]; } for(int i = n - 1; i > 0; --i) if(use[i] && a[i] == a[i - 1]) use[i - 1] = true; printf("%d", n - dp[n]); for(int i = 0; i < n; ++i) ans[a[i].id] = !use[i]; for(int i = 1; i <= n; ++i) if(ans[i]) printf(" %d", i); puts("");}int main() { while(scanf("%d", &n) != EOF) { for(int i = 0; i < n; ++i) { int x, y; scanf("%d%d", &x, &y); a[i].l = x + 1; a[i].r = n - y; if(x + y >= n) a[i].r = n + 1; a[i].pow = 1; a[i].id = i + 1; } sort(a, a + n); for(int i = 0; i < n - 1; ++i) if(a[i] == a[i + 1]) a[i + 1].pow += a[i].pow; for(int i = 0; i < n; ++i) a[i].pow = min(a[i].pow, a[i].r - a[i].l + 1); solve(); output(); }}
