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We can, of course, have an array of hierarchical records; inventory is such an array. We can access the year that the first machine was purchased using the following expression: |
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inventory[0].purchaseDate.year |
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And here is a code segment that prints out the ID number and the year of purchase of each machine that has a failure rate of more than 8 percent: |
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for (counter = 0; counter < NUM_MACHINES; counter++)
if (inventory[counter].history.failRate > 0.08)
cout << inventory[counter].idNumber <<
<< inventory[counter].purchaseDate.year << endl; |
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In Chapter 11, we presented a diagram (Figure 11-2) showing the structured types available in C++. We repeat this diagram in Figure 14-5. |
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So far we have discussed two of the four structured types: arrays and structs. We now look briefly at union types. The fourth structured type the classis the topic of Chapter 15. |
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In C++, a union is defined to be a struct that holds only one of its members at a time during program execution. Here is a declaration of a union type and a union variable: |
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union WeightType
{
long wtInOunces;
int wtInPounds;
float wtInTons;
}; |
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Figure 14-5
C++ Structured Types |
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