import macros;macro ImportExpand(s:untyped):untyped = parseStmt($s[2])
# source: https://github.com/kemuniku/cplib/tree/main/src/cplib/tmpl/citrus.nim
ImportExpand "cplib/tmpl/citrus" <=== "when not declared CPLIB_TMPL_CITRUS:\n    const CPLIB_TMPL_CITRUS* = 1\n    {.warning[UnusedImport]: off.}\n    {.hint[XDeclaredButNotUsed]: off.}\n    import os\n    import algorithm\n    import sequtils\n    import tables\n    import macros\n    import std/math\n    import sets\n    import strutils\n    import strformat\n    import sugar\n    import streams\n    import deques\n    import bitops\n    import heapqueue\n    import options\n    import hashes\n    const MODINT998244353* = 998244353\n    const MODINT1000000007* = 1000000007\n    when not declared CPLIB_UTILS_CONSTANTS:\n        const CPLIB_UTILS_CONSTANTS* = 1\n        const INF32*: int32 = 100100111.int32\n        const INF64*: int = int(3300300300300300491)\n    \n    const INFL = INF64\n    type double* = float64\n    let readNext = iterator(getsChar: bool = false): string {.closure.} =\n        while true:\n            var si: string\n            try: si = stdin.readLine\n            except EOFError: yield \"\"\n            for s in si.split:\n                if getsChar:\n                    for i in 0..<s.len():\n                        yield s[i..i]\n                else:\n                    if s.isEmptyOrWhitespace: continue\n                    yield s\n    proc input*(t: typedesc[string]): string = readNext()\n    proc input*(t: typedesc[char]): char = readNext(true)[0]\n    proc input*(t: typedesc[int]): int = readNext().parseInt\n    proc input*(t: typedesc[float]): float = readNext().parseFloat\n    macro input*(t: typedesc, n: varargs[int]): untyped =\n        var repStr = \"\"\n        for arg in n:\n            repStr &= &\"({arg.repr}).newSeqWith \"\n        parseExpr(&\"{repStr}input({t})\")\n    macro input*(ts: varargs[auto]): untyped =\n        var tupStr = \"\"\n        for t in ts:\n            tupStr &= &\"input({t.repr}),\"\n        parseExpr(&\"({tupStr})\")\n    macro input*(n: int, ts: varargs[auto]): untyped =\n        for typ in ts:\n            if typ.typeKind != ntyAnything:\n                error(\"Expected typedesc, got \" & typ.repr, typ)\n        parseExpr(&\"({n.repr}).newSeqWith input({ts.repr})\")\n    proc `fmtprint`*(x: int or string or char or bool): string = return $x\n    proc `fmtprint`*(x: float or float32 or float64): string = return &\"{x:.16f}\"\n    proc `fmtprint`*[T](x: seq[T] or Deque[T] or HashSet[T] or set[T]): string = return x.toSeq.join(\" \")\n    proc `fmtprint`*[T, N](x: array[T, N]): string = return x.toSeq.join(\" \")\n    proc `fmtprint`*[T](x: HeapQueue[T]): string =\n        var q = x\n        while q.len != 0:\n            result &= &\"{q.pop()}\"\n            if q.len != 0: result &= \" \"\n    proc `fmtprint`*[T](x: CountTable[T]): string =\n        result = x.pairs.toSeq.mapIt(&\"{it[0]}: {it[1]}\").join(\" \")\n    proc `fmtprint`*[K, V](x: Table[K, V]): string =\n        result = x.pairs.toSeq.mapIt(&\"{it[0]}: {it[1]}\").join(\" \")\n    proc print*(prop: tuple[f: File, sepc: string, endc: string, flush: bool], args: varargs[string, `fmtprint`]) =\n        for i in 0..<len(args):\n            prop.f.write(&\"{args[i]}\")\n            if i != len(args) - 1: prop.f.write(prop.sepc) else: prop.f.write(prop.endc)\n        if prop.flush: prop.f.flushFile()\n    proc print*(args: varargs[string, `fmtprint`]) = print((f: stdout, sepc: \" \", endc: \"\\n\", flush: false), args)\n    const LOCAL_DEBUG{.booldefine.} = false\n    macro getSymbolName(x: typed): string = x.toStrLit\n    macro debug*(args: varargs[untyped]): untyped =\n        when LOCAL_DEBUG:\n            result = newNimNode(nnkStmtList, args)\n            template prop(e: string = \"\"): untyped = (f: stderr, sepc: \"\", endc: e, flush: true)\n            for i, arg in args:\n                if arg.kind == nnkStrLit:\n                    result.add(quote do: print(prop(), \"\\\"\", `arg`, \"\\\"\"))\n                else:\n                    result.add(quote do: print(prop(\": \"), getSymbolName(`arg`)))\n                    result.add(quote do: print(prop(), `arg`))\n                if i != args.len - 1: result.add(quote do: print(prop(), \", \"))\n                else: result.add(quote do: print(prop(), \"\\n\"))\n        else:\n            return (quote do: discard)\n    proc `%`*(x: SomeInteger, y: SomeInteger): int =\n        result = x mod y\n        if y > 0 and result < 0: result += y\n        if y < 0 and result > 0: result += y\n    proc `//`*(x: SomeInteger, y: SomeInteger): int =\n        result = x div y\n        if y > 0 and result * y > x: result -= 1\n        if y < 0 and result * y < x: result -= 1\n    proc `^`*(x: SomeInteger, y: SomeInteger): int = x xor y\n    proc `&`*(x: SomeInteger, y: SomeInteger): int = x and y\n    proc `|`*(x: SomeInteger, y: SomeInteger): int = x or y\n    proc `>>`*(x: SomeInteger, y: SomeInteger): int = x shr y\n    proc `<<`*(x: SomeInteger, y: SomeInteger): int = x shl y\n    proc `%=`*(x: var SomeInteger, y: SomeInteger): void = x = x % y\n    proc `//=`*(x: var SomeInteger, y: SomeInteger): void = x = x // y\n    proc `^=`*(x: var SomeInteger, y: SomeInteger): void = x = x ^ y\n    proc `&=`*(x: var SomeInteger, y: SomeInteger): void = x = x & y\n    proc `|=`*(x: var SomeInteger, y: SomeInteger): void = x = x | y\n    proc `>>=`*(x: var SomeInteger, y: SomeInteger): void = x = x >> y\n    proc `<<=`*(x: var SomeInteger, y: SomeInteger): void = x = x << y\n    proc `[]`*(x, n: int): bool = (x and (1 shl n)) != 0\n    proc `[]=`*(x: var int, n: int, i: bool) =\n        if i: x = x or (1 << n)\n        else: (if x[n]: x = x xor (1 << n))\n    proc pow*(a, n: int, m = INF64): int =\n        var\n            rev = 1\n            a = a\n            n = n\n        while n > 0:\n            if n % 2 != 0: rev = (rev * a) mod m\n            if n > 1: a = (a * a) mod m\n            n >>= 1\n        return rev\n    when not declared CPLIB_MATH_ISQRT:\n        const CPLIB_MATH_ISQRT* = 1\n        proc isqrt*(n: int): int =\n            var x = n\n            var y = (x + 1) shr 1\n            while y < x:\n                x = y\n                y = (x + n div x) shr 1\n            return x\n    \n    proc chmax*[T](x: var T, y: T): bool {.discardable.} = (if x < y: (x = y; return true; ) return false)\n    proc chmin*[T](x: var T, y: T): bool {.discardable.} = (if x > y: (x = y; return true; ) return false)\n    proc `max=`*[T](x: var T, y: T) = x = max(x, y)\n    proc `min=`*[T](x: var T, y: T) = x = min(x, y)\n    proc at*(x: char, a = '0'): int = int(x) - int(a)\n    proc Yes*(b: bool = true): void = print(if b: \"Yes\" else: \"No\")\n    proc No*(b: bool = true): void = Yes(not b)\n    proc YES_upper*(b: bool = true): void = print(if b: \"YES\" else: \"NO\")\n    proc NO_upper*(b: bool = true): void = Yes_upper(not b)\n    const DXY* = [(0, -1), (0, 1), (-1, 0), (1, 0)]\n    const DDXY* = [(1, -1), (1, 0), (1, 1), (0, -1), (0, 1), (-1, -1), (-1, 0), (-1, 1)]\n    macro exit*(statement: untyped): untyped = (quote do: (`statement`; quit()))\n    proc initHashSet[T](): Hashset[T] = initHashSet[T](0)\n"
# source: https://github.com/kemuniku/cplib/tree/main/src/cplib/math/primefactor.nim
ImportExpand "cplib/math/primefactor" <=== "when not declared CPLIB_MATH_PRIMEFACTOR:\n    const CPLIB_MATH_PRIMEFACTOR* = 1\n    when not declared CPLIB_MATH_INNER_MATH:\n        const CPLIB_MATH_INNER_MATH* = 1\n        proc add*(a, b, m: int): int {.importcpp: \"((__int128)(#) + (__int128)(#)) % (__int128)(#)\", nodecl.}\n        proc mul*(a, b, m: int): int {.importcpp: \"(__int128)(#) * (__int128)(#) % (__int128)(#)\", nodecl.}\n    \n    when not declared CPLIB_MATH_ISPRIME:\n        const CPLIB_MATH_ISPRIME* = 1\n        when not declared CPLIB_MATH_POWMOD:\n            const CPLIB_MATH_POWMOD* = 1\n            proc powmod*(a, n, m: int): int =\n                var\n                    rev = 1\n                    a = a\n                    n = n\n                while n > 0:\n                    if n mod 2 != 0: rev = mul(rev, a, m)\n                    if n > 1: a = mul(a, a, m)\n                    n = n shr 1\n                return rev\n        \n        proc isprime*(N: int): bool =\n            let bases = [2, 325, 9375, 28178, 450775, 9780504, 1795265022]\n            if N == 2:\n                return true\n            if N < 2 or (N and 1) == 0:\n                return false\n            let N1 = N-1\n            var d = N1\n            var s = 0\n            while (d and 1) == 0:\n                d = d shr 1\n                s += 1\n            for a in bases:\n                var t: int\n                if a mod N == 0:\n                    continue\n                t = powmod(a, d, N)\n                if t == 1 or t == N1:\n                    continue\n                block test:\n                    for _ in 0..<(s-1):\n                        t = powmod(t, 2, N)\n                        if t == N1:\n                            break test\n                    return false\n            return true\n    \n    when not declared CPLIB_STR_RUN_LENGTH_ENCODE_UTILS:\n        const CPLIB_STR_RUN_LENGTH_ENCODE_UTILS* = 1\n        import sequtils\n        proc run_length_encode*[T](a: seq[T]): seq[(T, int)] =\n            for i in 0..<len(a):\n                if result.len == 0:\n                    result.add((a[i], 1))\n                    continue\n                if result[^1][0] == a[i]: result[^1][1] += 1\n                else: result.add((a[i], 1))\n    \n        proc run_length_encode*(s: string): seq[(char, int)] =\n            var a = s.items.toSeq\n            return run_length_encode(a)\n    \n    import random\n    import std/math\n    import algorithm\n    import tables\n\n    randomize()\n    proc find_factor(n: int): int =\n        if not ((n and 1) != 0): return 2\n        if isprime(n): return n\n        const m = 128\n        while true:\n            var x, ys, q, r, g = 1\n            var rnd, y = rand(0..n-3) + 2\n            proc f(x: int): int = add(mul(x, x, n), rnd, n)\n            while g == 1:\n                x = y\n                for i in 0..<r: y = f(y)\n                for k in countup(0, r-1, m):\n                    ys = y\n                    for _ in 0..<min(m, r-k):\n                        y = f(y)\n                        q = mul(q, abs(x-y), n)\n                    g = gcd(q, n)\n                    if g != 1: break\n                r = r shl 1\n            if g == n:\n                g = 1\n                while g == 1:\n                    ys = f(ys)\n                    g = gcd(n, abs(x - ys))\n            if g < n:\n                if isprime(g): return g\n                elif isprime(n div g): return n div g\n                return find_factor(g)\n\n    proc primefactor*(n: int, sorted: bool = true): seq[int] =\n        var n = n\n        while n > 1 and not isprime(n):\n            var p = find_factor(n)\n            while n mod p == 0:\n                result.add(p)\n                n = n div p\n        if n > 1: result.add(n)\n        if sorted: return result.sorted\n\n    proc primefactor_table*(n: int): Table[int, int] =\n        for p in primefactor(n):\n            if p in result: result[p] += 1\n            else: result[p] = 1\n\n    proc primefactor_tuple*(n: int): seq[(int, int)] = primefactor(n, true).run_length_encode\n"

# {.checks: off.}

var x = input(int)
if x == 1:
    print(2)
    print(1, 2)
    print("b", "g")
    quit()
var po = primefactor(x, true)
var p = newSeq[int]()
for i in 0..<po.len:
    if po[i] == 2 and p.len > 0 and p[^1] == 2:
        p[^1] = 4
    else:
        p.add(po[i])
var ans = 0
var n = p.len
for i in 0..<n:
    ans += p[i] + 1
if ans > 2 * pow(10, 5):
    print(-1)
    quit()

var e = newSeq[(int, int)]()
var c = newSeq[char]()
for i in 0..<p.len:
    var x = p[i]
    var s = c.len + 1
    c.add("b")
    for j in 0..<x:
        e.add (s, s + j + 1)
        c.add("g")
    if i != p.len - 1:
        debug(c)
        e.add (s, c.len + 1)
print(c.len)
for (u, v) in e:
    print(u, v)
print(c)