Accessing strings contained in slice

I am working on some coding exercises to better understand Go. A given exercise instructs me to create a program that will accept user input as follows:

• The first line specifies how many strings will be provided as input on separate lines
• The subsequent N lines will each be single strings

I am to output the characters corresponding to even and odd indices of each string separated by a space, and each string on it's separate line.

Example Input:

2
foo_bar
fizz_buzz

Should Output:

fobr o_a
fz_uz izbz

But in my program accessing a slice of strings returns an empty string:

package main

import (
	"fmt"
)

func main() {
	// read an integer describing how many strings will be input
	var num_strings int
	fmt.Scan(&num_strings)

	// create a slice of strings to hold provided strings
	strings := make([]string, num_strings)

	// add provided strings to slice
	for i := 0; i < num_strings; i++ {
		var temp string
		fmt.Scan(&temp)
		strings = append(strings, temp)
	}

	// check that strings have been appended
	fmt.Println("Strings:", strings)

	// check that strings can be accessed
	for i := 0; i < num_strings; i++ {
		fmt.Println(i, strings[i]) // only i prints, not strings[i]
	}

	// loop over all strings
	for i := 0; i < num_strings; i++ {

		// if string index is even print the char
		for index, val := range strings[i] {
			if index%2 == 0 {
				fmt.Print(val)
			}
		}

		fmt.Print(" ")

		// if string index is odd print the char
		for index, val := range strings[i] {
			if index%2 != 0 {
				fmt.Print(val)
			}
		}

		// newline for next string
		fmt.Print("\n")
	}
}

2
foo_bar
fizz_buzz
Strings: [  foo_bar fizz_buzz]
0 
1 
 
 

Because when you make your strings slice, you're creating a slice with both a capacity and length of n. So when you append to it, you're increasing the length of the slice:

Change this bit of code:

// create a slice of strings to hold provided strings
strings := make([]string, num_strings)

// add provided strings to slice
for i := 0; i < num_strings; i++ {
  var temp string
  fmt.Scan(&temp)
  strings = append(strings, temp)
}

to either:

// create a slice of strings to hold provided strings
strings := []{}

// add provided strings to slice
for i := 0; i < num_strings; i++ {
  var temp string
  fmt.Scan(&temp)
  strings = append(strings, temp)
}

Or

// create a slice of strings to hold provided strings
strings := make([]string, num_strings)

// add provided strings to slice
for i := 0; i < num_strings; i++ {
  var temp string
  fmt.Scan(&temp)
  strings[i] = temp
}

And you should be good.