Array Index Out of bounds, line error stated;

Line error is 197; I have no clue why, as i set there value up the first time, anything above 150 does not work, no clue?

using UnityEngine; using System.Collections;

public class GrassGaneration : MonoBehaviour {

 public GameObject[] blockidset = new GameObject[3];
 public Transform grasstrans;//-1 = air(nothing), 0 = grass, 1 = dirt, 2 = stone
 public Transform dirttrans;
 private int count;
 public int lastlongelevation;
 private int[] grassmap; //= new int[50];
 private int[] elevationmap; //= new int[50];
 private int[,] blockid; //=  new int [50,100];
 public int elevationnoise;
 public int elevationscalenoise;
 //private int randommineral;
 //private int oresizex;
 //private int oresizey;
 //private int[] orenoise = new int[40];
 //private int scaleore;
 //private int randomore2;
 //private int orechange;
 private int numbercount = 1;
 private int max;
 public int maplength;

 void Start()
 {

     grassmap = new int[maplength];
     elevationmap = new int[maplength];
     blockid = new int[maplength, 100];

     setblockidtozero();

     grassmapcreate();
     grassmapsmooth();

     creatorelevationmap();

     grassmapelevationmapcombine();

     findmaxgrassmapvalue();

     setblockid();

     createblocks();


 }



 // Update is called once per frame
 void Update()
 {

 }

 void creatorelevationmap() {

     int chanceofchange = 0;
     int scale = 0;
     int updown = 0;
     int length = 0;

     for (int q = 0; q < maplength; q++)
     {
         
         if (chanceofchange == 1)
         {
             length = (int)Mathf.Round(Random.Range(Mathf.Round(lastlongelevation/2), lastlongelevation));
             scale = (int)Mathf.Round(Random.Range(0, elevationscalenoise));
             updown = (int)Mathf.Round(Random.Range(0, 2)) - 1;
             chanceofchange = 0;
         }

         if (length == 0)
         {
             chanceofchange = (int)Mathf.Round(Random.Range(0, elevationnoise));
             scale = 0;
         }
         else if (length != 0)
         {
             scale = (int)Mathf.Round(Random.Range(0, elevationscalenoise));
             length = length - 1;
         }

         
         
         

         
         if (q == 0) {
             if (updown == 0)
             {
                 elevationmap[q] = scale;
             }
             else {
                 elevationmap[q] = -scale;
             }
         
     } else {
             if (updown == 0)
             {
                 elevationmap[q] = elevationmap[q - 1] + scale;
         }
             else {
                 elevationmap[q] = elevationmap[q - 1] - scale;
             }
         }

         if (elevationmap[q] + grassmap[q] < 19)
         {
             updown = 0;
         }

     }
 }
 void setblockidtozero()
 {
     for (int bb = 0; bb < maplength; bb++)
     {
         for (int bv = 0; bv < 100; bv++)
         {
             blockid[bb, bv] = -1;
         }
     }
 }
 void grassmapcreate()
 {
     grassmap[0] = (int)Mathf.Round(Random.Range(0, 3)) - 1;
     for (int c = 1; c < maplength; c++)
     {
         numbercount++;
         count = (int)Mathf.Round(Random.Range(0, 3));
         if (grassmap[c - 1] == -4)
         {
             grassmap[c] = grassmap[c - 1] + count;
         }
         else if (grassmap[c - 1] == 4)
         {
             grassmap[c] = grassmap[c - 1] + count - 2;
         }
         else {
             grassmap[c] = grassmap[c - 1] + count - 1;
         }

     }
 }

 void grassmapsmooth()
 {
     for (int u = 1; u < maplength - 1; u++)
     {
         if (grassmap[u - 1] == grassmap[u + 1])
         {
             if (grassmap[u] + 1 == grassmap[u - 1])
             {
                 grassmap[u] = grassmap[u - 1];
             }
             else if (grassmap[u] - 1 == grassmap[u - 1])
             {
                 grassmap[u] = grassmap[u - 1];
             }
         }
     }
 }

 void grassmapelevationmapcombine()
 {
     for (int y = 0; y < maplength; y++)
     {
         grassmap[y] = grassmap[y] + elevationmap[y];
     }
 }

 void findmaxgrassmapvalue()
 {
     max = grassmap[0];
     for (int p = 1; p < grassmap.Length; p++)
     {

         if (grassmap[p] > grassmap[p - 1])
         {
             max = grassmap[p];
         }

     }
 }

 void setblockid()
 {
     for (int b = 0; b < maplength; b++)
     {
         blockid[b, grassmap[b] + 60] = 0;

         for (int n = 0; n < (grassmap[b] + 60); n++)
         {
             if (n > 40)
             {
                 blockid[b, n] = 1;

             }
             else {
                 blockid[b, n] = 2;

             }

         }
     }
 }

 void createblocks()
 {
     for (int b1 = 0; b1 < maplength; b1++)
     {
         for (int n1 = 0; n1 < 100; n1++)
         {
             if (blockid[b1, n1] == -1)
             {

             }
             else {
                 Instantiate(blockidset[blockid[b1, n1]], new Vector2(8 * b1, (n1 - 60) * 8), dirttrans.rotation);
             }

         }
     }
 }

 

}

put this into your code editor to see the line numbers, i couldn't get "printscreen" to work on here.