why does my for loop skips first step
<p>here is my code....</p>

<pre><code>import java.util.*;

public class lozanosjfver21 {
  public static void main(String args[]) {
    Scanner sc = new Scanner(System.in);
    System.out.println("enter the processes");

    int nop=sc.nextInt();
    int z=nop;
    int table1[][] = new int[z][6];
    int table2[][] = new int[z][6];

    int total = 0;
    boolean con[] = new boolean[z];
    boolean fin[] = new boolean[z];
    boolean lowest[] = new boolean[z];

    for(int a=0;a&lt;z;a++) {
      System.out.print("Input ARRIVAL TIME and BURST TIME for process"+(a+1)+":");
      StringTokenizer st = new StringTokenizer(sc.nextLine());
      int b=1;
      while(st.hasMoreTokens()) {
        table1[a][b] = Integer.parseInt(""+st.nextToken());
        table2[a][b] = table1[a][b];
        b++;
      }
      table1[a][0] = (a+1);
      table2[a][0] = table1[a][0];
      total += table1[a][2];
      con[a] = false;
      fin[a] = false;
      lowest[a] = false;
    }
    //System.out.println(""+total);
    String str[] = new String[total];

    for(int c=0;c&lt;total;c++) {
      /*
       * determines if a row should be considered
       * (! done and within the current time)
       */
      for(int d=0;d&lt;z;d++) {
        if (table1[d][1]&lt;=c&amp;&amp;!fin[d]) {
          con[d] = true;
        }
      }

      /*
       * determines the first low value
       * (the basis for the determining the
       * lowest value in each loop)
       */
      int low=0;
      for(int j=0;j&lt;z;j++) {
        if(con[j]) {
          low = table1[j][2];
          break;
        }
      }

      /*
       * determines the lowest value among
       * the values considered
       */
      for(int k=0;k&lt;z;k++) {
        if(table1[k][2]&lt;low&amp;&amp;con[k]) {
          low = table1[k][2];
        }
      }

      /*
       * marks the lowest
       */
      for(int l=0;l&lt;z;l++) {
        if(table1[l][2]==low) {
          lowest[l] = true;
          break;
        }
      }

      //this part does all the actions
      for(int f=0;f&lt;z;f++) {
        if(lowest[f]) {
          table1[f][2] -= 1;
          if(table1[f][2]==0) {
            fin[f] = true;
            str[c] = ""+(f+1);
            break;
          }
        }
      }

      if(str[c]==null) str[c] = "0";

      //clearing
      for(int p=0;p&lt;z;p++) {
        lowest[p] = false;
        con[p] = false;
      }
    }

    for(int n=0;n&lt;total;n++) {
      if(str[n]!="0") {
        table2[Integer.parseInt(str[n])-1][5] = n+1;
      }
    }
    for(int t=0;t&lt;nop;t++) {
      table2[t][4] = table2[t][5] - table2[t][1];
      table2[t][3] = table2[t][4] - table2[t][2];
    }

    System.out.println("\nP\tAT\tBT\tWT\tTT");
    for(int x=0;x&lt;z;x++) {
      System.out.println(""+table2[x][0]+"\t"+table2[x][1]+"\t"+table2[x][2]+"\t"+table2[x][3]+"\t"+table2[x][4]+"\t");
    }
}
</code></pre>

<p>and here is the output:</p>

<pre><code>enter the processes
4
Input ARRIVAL TIME and BURST TIME for process1:Input ARRIVAL TIME and BURST TIME for process2:0 2
Input ARRIVAL TIME and BURST TIME for process3:2 6
Input ARRIVAL TIME and BURST TIME for process4:6 5

P   AT  BT  WT  TT
1   0   0   0   0   
2   0   2   -2  0   
3   2   6   -8  -2  
4   6   5   -11 -6  

Process completed.
</code></pre>
