Why Does `pow(10,5)` Sometimes Return 9999 Instead of 10000 in C ?

Why Does pow(10,5) Equal 9,999 in C ?

When you invoke the pow function in C to calculate a power operation, the return value can potentially have a floating-point precision. However, in certain cases, the result may be truncated when assigned to an integer variable.

In the example provided:

const int sections = 10;

for(int t= 0; t < 5; t++){
   int i = pow(sections, 5- t -1);  
   cout << i << endl;
}

The repeated calculations of pow(sections, 5- t -1) using the integer sections and the integer subtraction will result in integer values. When these values are used to compute the power, the result may be a floating-point value with a fractional part.

Assigning this floating-point value to the integer variable i triggers truncation. For instance, if pow(sections, 5- t -1) evaluates to 9999.9999, the fractional part will be discarded, leaving you with i = 9999.

To avoid this issue, you can directly use the pow function within the output statement:

for(int t = 0; t < 5; t++){
    cout << pow(sections,5-t-1) << endl; 
}

In this case, the result of pow(sections,5-t-1) is printed directly without the need for an intermediate integer variable, ensuring the correct values are displayed.

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