UVa 11368

according to this solution...
Solution
and this tutorial on Binary Indexed Tree...
Tutorial
binary indexed tree in this problem is used to get V
state:
    dp[i] - minimum dolls sequence at position i, the same with LIS's state
transition:
    dp[i]=max(dp[i], V+1)
    V is max(dp[k]), for all k<i

/* UVas */
/*****************************************************************************/
struct doll {
    int d[2];
    inline bool operator<(const doll &o) const {
        if (d[0]==o.d[0])
            return d[1]>o.d[1];
        return d[0]<o.d[0];
    }
} D[20000];
int t, m;
int read(int i, int *a) {
    int r=0;
    while (i) {
        r=max(r, a[i]);
        i-=i&(-i);
    }
    return r;
}
void updt(int i, int *a, int l, int arg) {
    while (i<=l) {
        a[i]=max(a[i], arg);
        i+=i&(-i);
    }
}
int main(void) {
    scanf("%d", &t);
    while (t--) {
        scanf("%d", &m);
        for (int i=0; i<m; i++)
            scanf("%d %d", &D[i].d[0], &D[i].d[1]);
        sort(D, D+m);
        int d[20000]={};
        int h[2][10001]={};
        int r=0;
        for (int i=0; i<m; i++) {
            for (int j=0; j<2; j++) {
                int f=read(10001-D[i].d[j], h[j]);
                d[i]=max(d[i], f+1);
                updt(10001-D[i].d[j], h[j], 10001, d[i]);
            }
            r=max(r, d[i]);
        }
        printf("%d\n", r);
    }
}
/*****************************************************************************/