#include 
     
      #define pb push_back#define _for(i,a,b) for(int i = (a);i < (b);i ++)#define INF 0x3f3f3f3f#define sz size()using namespace std;const int maxn = 50003;typedef long long ll;struct Mouse{    int w;    int s;    int in;    bool operator < (Mouse b)    {        if(w!=b.w)        return w < b.w;        return s > b.s;    }};int main(){    Mouse a[1003];    int aend = 0;    int c,d;    while(~scanf("%d %d",&c,&d))    {        a[aend].w = c;        a[aend].in = aend+1;        a[aend++].s = d;    }    sort(a,a+aend);    int dp[aend];        _for(i,0,aend)        dp[i] = 1;    for(int i = 1;i < aend;i ++)        for(int j = 0;j < i;j ++)        {            if(a[i].w==a[j].w)                continue;            if(a[i].s < a[j].s)                dp[i] = max(dp[i],dp[j]+1);        }    vector
      
        rrnt;        int ii;    int rr = 0;    for(int i = aend-1;i >= 0;i --)        if(rr < dp[i])        {            ii = i;            rr = dp[i];        }    cout << dp[ii] << endl;        int rnt = dp[ii];    rrnt.pb(a[ii].in);    for(int i = ii-1;i >= 0;i --)        if(dp[i]==rnt-1)        {            rnt --;            rrnt.pb(a[i].in);        }    for(int i = rrnt.size()-1;i >= 0;i --)        cout << rrnt[i] << endl;    return 0;}