Shell script Programming Exercises

Create loops in shell scripts to append echo content redirection to a file

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The file is empty before running the script with the contents

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Creating an array in a shell script

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Results:

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Use three loops to iterate through an array and initialize it directly using parentheses to set content.

1.${#arr [@ or *]} indicates the number of elements in the array

2. You can use ${arr[when you take each element of an array]}, just as you access array elements through array subscripts in C

3. You can use ${arr[@]} or use ${arr[*]} to display all elements in the array

4. arrays can accept any type of data, or directly to a certain location of the array directly assigned to the operation, or the non-contiguous array initialization, where the contents of the non-contiguous arrays are empty

1. Use shell scripts to write simple summation operations

The process of displaying data accumulation 1+2+3+4+...+n

Method 1. Use the printf function to print content, which differs from echo in that Echo wraps the line, and that the function does not wrap

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Method 2. Define a string that is appended to the back, minus the + sign when appended to the last number

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Both methods run the same result

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Method 3: Summing with recursion

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Results:

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The Linux system has a BC calculator, which can be calculated

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2. A simple progress bar

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Results:

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3. Case and sequence conversion of strings

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Results:

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Using the cut tool to intercept a specified range of strings in a single character read, the TR tool can convert the case of a character and redirect the hit to the marked content to another file

4. Find the maximum, minimum, and average of three numbers

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Results:

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5. Fibonacci Sequence

Method 1. Use three numbers for conduction

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Method 2. Borrowing Array evaluation

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Method 3. Using recursion

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Results:

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Shell script Programming Exercises