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/*                                                                                */
/*                         C Programs from Chapter 1 of                           */
/*            Data Structures, Algorithms and Software Principles in C            */
/*                             by Thomas A. Standish                              */
/*                                                                                */
/*          Copyright (C) 1995, Addison-Wesley, Inc., all rights reserved         */
/*                                                                                */
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   |   #define MaxIndex 100
   |
   |   int Find(int A[])                    /* Find operates on integer arrays, A */
   |   {   
 5 |      int j;                     /* j is an index variable used in the search */
   |   
   |      for (j = 0; j<MaxIndex; ++j){   /* search upward starting at position 0 */
   |         if (A[j] < 0) {                               /* if A[j] is negative */
   |            return j;                     /* return its index j as the result */
10 |         }
   |      }
   |      
   |      return -1;               /* return -1 if no negative integers were found*/
   |   }
15 |
   |   int main(void)
   |   {      
   |      int   A[MaxIndex];                   /* declare A to be an integer array*/
   |      int   i;          /* let i be an index variable used for initialization */
20 |   
   |     /* Initialize array A to squares of integers. Then make A[17] negative. */
   |      for ( i = 0; i < MaxIndex; ++i ) A[i] = i*i;   
   |      A[17] = - A[17];
   |
25 |     /* Print test results */
   |      printf("First negative integer in A found at index = %2d.\n",Find(A));
   |   }

Program 1.3 Finding the First Negative Integer in an Integer Array

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      |   int Find(SearchArray A)
      |   {
      |      int i = 0;
      |
    5 |      while ((A[i] >= 0) && (i < MaxIndex)) {
      |         ++i;
      |      }
      |      
      |      return (i < MaxIndex) ? i : -1;
   10 |   }

Program for Exercise 1 on page 21

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      |   int Find( int A[ ] )
      |   {   
      |      int i, result;
      |
    5 |      result = -1;
      |      for (i = MaxIndex-1; i >= 0; --i) if (A[i] < 0) result = i;
      |      return result;
      |   }


Program for Exercise 2 on page 21

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