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package main

import (
	"fmt"
	"os"
)

type point struct {
	x, y int
}

func main() {

	p := point{1, 2}
	fmt.Printf("struct1: %v\n", p)  // struct1: {1 2}
	fmt.Printf("struct2: %+v\n", p) // struct2: {x:1 y:2}
	fmt.Printf("struct3: %#v\n", p) // struct3: main.point{x:1, y:2}

	fmt.Printf("type: %T\n", p)    // type: main.point
	fmt.Printf("bool: %t\n", true) // bool: true
	fmt.Printf("int: %d\n", 123)   // int: 123

	fmt.Printf("bin: %b\n", 14)      // bin: 1110
	fmt.Printf("char: %c\n", 33)     // char: !
	fmt.Printf("hex: %x\n", 456)     // hex: 1c8
	fmt.Printf("float1: %f\n", 78.9) // float1: 78.900000

	fmt.Printf("float2: %e\n", 123400000.0) // float2: 1.234000e+08
	fmt.Printf("float3: %E\n", 123400000.0) // float3: 1.234000E+08

	fmt.Printf("str1: %s\n", "\"string\"") // str1: "string"
	fmt.Printf("str2: %q\n", "\"string\"") // str2: "\"string\""
	fmt.Printf("str3: %x\n", "hex this")   // str3: 6865782074686973

	fmt.Printf("pointer: %p\n", &p) // pointer: 0xc0000140c0

	fmt.Printf("width1: |%6d|%6d|\n", 12, 345)         // width1: |    12|   345|
	fmt.Printf("width2: |%6.2f|%6.2f|\n", 1.2, 3.45)   // width2: |  1.20|  3.45|
	fmt.Printf("width3: |%-6.2f|%-6.2f|\n", 1.2, 3.45) // width3: |1.20  |3.45  |
	fmt.Printf("width4: |%6s|%6s|\n", "foo", "b")      // width4: |   foo|     b|
	fmt.Printf("width5: |%-6s|%-6s|\n", "foo", "b")    // width5: |foo   |b     |

	s := fmt.Sprintf("sprintf: a %s", "string") // sprintf: a string
	fmt.Println(s)                              // io: an error

	fmt.Fprintf(os.Stderr, "io: an %s\n", "error")
}