Problem:
Score : 300 points

Problem Statement

Takahashi participated in a contest on AtCoder.

The contest had N problems.

Takahashi made M submissions during the contest.

The i-th submission was made for the p_i-th problem and received the verdict S_i (AC or WA).

The number of Takahashi's correct answers is the number of problems on which he received an AC once or more.

The number of Takahashi's penalties is the sum of the following count for the problems on which he received an AC once or more: the number of WAs received before receiving an AC for the first time on that problem.

Find the numbers of Takahashi's correct answers and penalties.

Constraints

N, M, and p_i are integers.

1 \leq N \leq 10^5

0 \leq M \leq 10^5

1 \leq p_i \leq N

S_i is AC or WA.

Input

Input is given from Standard Input in the following format:

N M
p_1 S_1
:
p_M S_M

Output

Print the number of Takahashi's correct answers and the number of Takahashi's penalties.

Sample Input 1

2 5
1 WA
1 AC
2 WA
2 AC
2 WA

Sample Output 1

2 2

In his second submission, he received an AC on the first problem for the first time. Before this, he received one WA on this problem.

In his fourth submission, he received an AC on the second problem for the first time. Before this, he received one WA on this problem.

Thus, he has two correct answers and two penalties.

Sample Input 2

100000 3
7777 AC
7777 AC
7777 AC

Sample Output 2

1 0

Note that it is pointless to get an AC more than once on the same problem.

Sample Input 3

6 0

Sample Output 3

0 0

Solution in Go (1.6) (judge verdict: Accepted)

package main

import (
	"bufio"
	"fmt"
	"math"
	"os"
	"sort"
	"strconv"
	"strings"
)

func main() {
	io := NewIo()
	defer io.Flush()

	_, m := io.Int(), io.Int()

	sub := make([][]int, m)

	for i := 0; i < m; i++ {
		p := io.Int()
		s := io.Next()
		if s == "AC" {
			sub[i] = []int{p, 1}
		} else {
			sub[i] = []int{p, 0}
		}
	}

	waCnt := map[int]int{}

	wa := 0
	ac := 0

	// fmt.Println(sub)
	for _, s := range sub {
		if s[1] == 1 && waCnt[s[0]] != -1 {
			ac++
			if cnt, ok := waCnt[s[0]]; ok {
				wa += cnt
			}
			waCnt[s[0]] = -1
		} else if waCnt[s[0]] != -1 {
			waCnt[s[0]]++
		}
	}

	fmt.Println(ac, wa)
}

type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buffer []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buffer = append(buffer, line...)
		if !isPrefix {
			break
		}
	}
	return string(buffer)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	r := io.tokens[io.nextToken]
	io.nextToken++
	return r
}

func (io *Io) Int() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Float() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) PrintLn(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntLn(a []int) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.PrintLn(b...)
}

func (io *Io) PrintStringLn(a []string) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.PrintLn(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func Abs(a int) int {
	if a >= 0 {
		return a
	} else {
		return -a
	}
}

func Pow(p, q int) int {
	return int(math.Pow(float64(p), float64(q)))
}

func Min(nums ...int) int {
	if len(nums) == 0 {
		panic("funciton min() requires at least one argument.")
	}
	res := nums[0]
	for i := 0; i < len(nums); i++ {
		res = int(math.Min(float64(res), float64(nums[i])))
	}
	return res
}

func Max(nums ...int) int {
	if len(nums) == 0 {
		panic("funciton max() requires at least one argument.")
	}
	res := nums[0]
	for i := 0; i < len(nums); i++ {
		res = int(math.Max(float64(res), float64(nums[i])))
	}
	return res
}

func SortAsc(a []int) []int {
	sort.Ints(a)
	return a
}

func SortDesc(a []int) []int {
	sort.Sort(sort.Reverse(sort.IntSlice(a)))
	return a
}

func GCD(a, b int) int {
	if b == 0 {
		return a
	}
	return GCD(b, a%b)
}

func LCM(a, b int) int {
	if a == 0 && b == 0 {
		return 0
	}
	return a * b / GCD(a, b)
}

func CumSum(nums []int) []int {
	sums := []int{0}

	for i := 0; i < len(nums); i++ {
		sums = append(sums, sums[i]+nums[i])
	}
	return sums
}

func BisectLeft(nums []int, left, right int, target int) int {
	if left == right {
		if nums[left] == target {
			return left
		} else if nums[left] < target {
			return left + 1
		} else {
			return left
		}
	}

	mid := (left + right) / 2
	if nums[mid] == target {
		return mid
	}

	if nums[mid] > target {
		return BisectLeft(nums, left, mid, target)
	} else if nums[mid] < target {
		return BisectLeft(nums, mid+1, right, target)
	}
	return 0
}

func Permutations(nums []int) [][]int {
	n := len(nums)
	if n == 0 {
		return [][]int{}
	}
	ans := [][]int{}

	for _, n := range nums {
		rest := remove(nums, n)
		lists := Permutations(rest)
		if len(lists) == 0 {
			lists = [][]int{nil}
		}

		for i := 0; i < len(lists); i++ {
			lists[i] = append(lists[i], n)
			ans = append(ans, lists[i])
		}
	}
	return ans
}

func remove(nums []int, target int) []int {
	result := []int{}
	for i := 0; i < len(nums); i++ {
		if nums[i] != target {
			result = append(result, nums[i])
		}
	}
	return result
}

func PowerSet(nums []int) [][]int {
	size := Pow(2, len(nums))
	result := make([][]int, size)

	idx := 0
	result[idx] = []int{}
	idx++

	for _, n := range nums {
		max := idx
		for i := 0; i < max; i++ {
			result[idx] = copyAndAppend(result[i], n)
			idx++
		}
	}

	return result
}

func copyAndAppend(nums []int, n int) []int {
	dst := make([]int, len(nums)+1)
	copy(dst, nums)
	dst[len(nums)] = n
	return dst
}

func Combination(nums []int, k int) [][]int {
	size := len(nums)
	result := make([][]int, CombinationCount(int64(len(nums)), int64(k), 10e9))
	bi := (1 << uint(k)) - 1
	max := 1 << uint(size)
	idx := 0

	for bi < max {
		flags := bi
		s := []int{}
		for _, n := range nums {
			if flags%2 != 0 {
				s = append(s, n)
			}
			flags /= 2
		}
		result[idx] = s
		idx++
		bi = Combination2NextIndex(bi)
	}
	return result
}

func Combination2NextIndex(n int) int {
	smallest := n & -n
	ripple := n + smallest
	newSmallest := ripple & -ripple
	ones := ((newSmallest / smallest) >> 1) - 1
	return ripple | ones
}

// CombinationCount はnCmを計算する関数。メモ化を使って計算量を削減する。
func CombinationCount(n, m, maxInput int64) int64 {
	memo := map[int64]map[int64]int64{}
	for i := int64(1); i <= maxInput*maxInput; i++ {
		memo[int64(i)] = map[int64]int64{}
	}
	return combinationCount(n, m, memo)
}
func combinationCount(n, m int64, memo map[int64]map[int64]int64) int64 {
	if n == m || m == 0 {
		return 1
	}

	left, lOK := memo[n-1][m-1]
	right, rOK := memo[n-1][m]

	if lOK && rOK {
		return left + right
	}

	if lOK {
		right = combinationCount(n-1, m, memo)
		memo[n-1][m] = right
		return left + right
	}

	if rOK {
		left = combinationCount(n-1, m-1, memo)
		memo[n-1][m-1] = left
		return left + right
	}

	left = combinationCount(n-1, m-1, memo)
	right = combinationCount(n-1, m, memo)
	memo[n-1][m-1] = left
	memo[n-1][m] = right
	return left + right
}

func Fact(n int) int {
	if n == 0 {
		return 1
	} else {
		return n * Fact(n-1)
	}
}

func Divisors(n int) []int {
	divisors := map[int]bool{}
	for i := 1; i < int(math.Sqrt(float64(n)))+1; i++ {
		if n%i == 0 {
			divisors[i] = true
			//divisors = append(divisors, i)
			if i != n {
				divisors[n/i] = true
				//divisors = append(divisors, n/i)
			}
		}

	}
	ans := []int{}
	for k := range divisors {
		ans = append(ans, k)
	}
	return ans
}