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CodeFu 2010 Results

Final Round Results

Goran's solution for 300: NumberSequence, written in Java, submitted on 09.05.2010 14:14:55

public class NumberSequence {

	  public int findDigit(int N) {
		  if(N==1)return 1;
		  if(N==2)return 1;
		  /*
		  int m=0;
		  int p=9;
		  for(int i=1; i<=5; i++){
			  m += i*(p*(p+1))/2;
			  System.out.println("i : "+i+ " m: "+m);
			  p *= 10;
		  }
	  */
		  int start;
		  if(N<=45){//one digit
			  start=1;
			  int n[] = {1,2,3,4,5,6,7,8,9};
			  int end=0, i, curr=0;
			  while(true){
				  for(i=0; i<=end; i++){
					  curr++;
					  if(curr==N) return n[i]; 
				  }
				  end++;
			  }
		  }
		  else if(N<=8235){ //two digits
			  start = 46;
			  int t=10;
			  for(int ii=start; ii<=8235; ii+=2){
				  
				  if(N == ii){
					  return t/10;
				  }
				  else if(N == ii+1){
					return t%10;  
				  }
				  t++;
			  }
		  }
		  else if(N<=1224585){ //three digits
			start=8236; 
			  int t=100;
			  for(int ii=start; ii<=8235; ii+=3){
				  
				  if(N == ii){
					  return t/100;
				  }
				  else if(N == ii+1){
					return (t/10)%10;  
				  }
				  else if(N == ii+2){
					return t%10;  
				  }
				  t++;
			  }

		  }
		  else if(N<=163242585){//four digits
			  start=1224585+1;
	
		  }
		  else if(N<=1000000000){//five digits
			  start=163242585+1;

		  }
		  
		  //System.out.println(m);
		  return 0;
	}
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		System.out.println(new NumberSequence().findDigit(46));
	}

}