Longest Increasing Subsequence

#include <cstdio>
#include <algorithm>
using namespace std;
int main(){
    int ar[]={2,3,1,4,7,8,10,2,3,9};
    int n=sizeof(ar)/sizeof(ar[0]);
    int i,c=1,mx=-1;
    for(i=1; i<n; i++){
        if (ar[i-1]<ar[i]) c++;
        else mx=max(mx,c),c=1;
    }
    mx=max(mx,c);
    printf("%d\n",mx);
}