18 February Apple Sequences

class Solution{   
public:
    int appleSequences(int n, int m, string arr){
        int start = 0, end = 0;
        int curr=0;
        int maxx=0;
        while(end<n){
            if(arr[end]=='A'){
                maxx=max(maxx, end-start+1);
            }
            if(arr[end]=='O'){
                curr++;
                if(curr>m){
                    while(start<end && arr[start]!='O')
                        start++;
                    start++;    
                }
                maxx=max(maxx, end-start+1);
            }
            end++;
        }
        return maxx;
    }
};