Prefix and Suffix Search

cs

public class WordFilter {

    private string[] _words; 
    public WordFilter(string[] words) {
        _words =words;
    }
    
    public int F(string prefix, string suffix) {
        int ans = -1;
        var prefixLength =prefix.Length;
        var suffixLength =suffix.Length;
        var prefixfound =-1;
        var suffixfound =-1;
        var result = new Dictionary<int,int>();
        for(var i =0; i< _words.Length; i++){
            
            var ismatch=true;
            if(_words[i].Length>= prefixLength){
                
                
                for(var idx =0; idx<prefixLength; idx++ ){
                    if(_words[i][idx] != prefix[idx]){
                        ismatch=false;
                        break;
                    }
                }
                 
                if(ismatch ){
                 // prefixfound = prefixLength; 
                    result[prefixLength] =i;
                 // ans = System.Math.Max(ans,i);
                    
                }
            }
            
            
            if(_words[i].Length>= suffixLength  && ismatch){
                 
                var wordIdx = _words[i].Length;
                for(var idx =0; idx < suffixLength ; idx++ ){
                    
                    if(_words[i][wordIdx - suffixLength + idx] != suffix[idx]){
                        ismatch=false;
                        break;
                    }
                }
                
                if(ismatch  ){
                    result[_words[i].Length] =i;
                    result[prefixLength] =i;
                  //suffixfound = _words[i].Length;
                //  ans = System.Math.Max(ans,i);
                    
                }
            }
        }
        
        return result.Count==0? -1 :  result[result.Keys.Max()];
    }
}

/**
 * Your WordFilter object will be instantiated and called as such:
 * WordFilter obj = new WordFilter(words);
 * int param_1 = obj.F(prefix,suffix);
 */

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