For problem statement at 0-999/700-799/700-709/704/problemD.txt this is a correct solution, but verifier at 0-999/700-799/700-709/704/verifierD.go ends with All tests passed can you fix the verifier? ```go
package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

var scanner *bufio.Scanner

func init() {
	scanner = bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	buf := make([]byte, 1024*1024)
	scanner.Buffer(buf, 10*1024*1024)
}

func nextInt() int {
	scanner.Scan()
	res, _ := strconv.Atoi(scanner.Text())
	return res
}

const INF = 1e9

type Point struct{ x, y int }

type Constraint struct{ t, l, d int }

type Edge struct {
	to, cap, flow, rev, id int
}

var g [][]Edge
var level []int
var ptr []int

func addEdge(u, v, cap, id int) {
	g[u] = append(g[u], Edge{v, cap, 0, len(g[v]), id})
	g[v] = append(g[v], Edge{u, 0, 0, len(g[u]) - 1, -1})
}

var q []int

func bfs(s, t int) bool {
	for i := range level {
		level[i] = -1
	}
	level[s] = 0
	q = append(q[:0], s)
	for len(q) > 0 {
		v := q[0]
		q = q[1:]
		for _, e := range g[v] {
			if e.cap-e.flow > 0 && level[e.to] == -1 {
				level[e.to] = level[v] + 1
				q = append(q, e.to)
			}
		}
	}
	return level[t] != -1
}

func dfs(v, t, pushed int) int {
	if pushed == 0 {
		return 0
	}
	if v == t {
		return pushed
	}
	for ; ptr[v] < len(g[v]); ptr[v]++ {
		e := &g[v][ptr[v]]
		tr := e.to
		if level[v]+1 != level[tr] || e.cap-e.flow == 0 {
			continue
		}
		push := pushed
		if e.cap-e.flow < push {
			push = e.cap - e.flow
		}
		p := dfs(tr, t, push)
		if p == 0 {
			continue
		}
		e.flow += p
		g[tr][e.rev].flow -= p
		return p
	}
	return 0
}

func dinic(s, t int) int {
	flow := 0
	for bfs(s, t) {
		for i := range ptr {
			ptr[i] = 0
		}
		for {
			pushed := dfs(s, t, INF)
			if pushed == 0 {
				break
			}
			flow += pushed
		}
	}
	return flow
}

func main() {
	if !scanner.Scan() {
		return
	}
	N, _ := strconv.Atoi(scanner.Text())
	M := nextInt()
	r := nextInt()
	b := nextInt()

	shields := make([]Point, N)
	mapX := make(map[int]int)
	mapY := make(map[int]int)

	for i := 0; i < N; i++ {
		shields[i].x = nextInt()
		shields[i].y = nextInt()
		if _, ok := mapX[shields[i].x]; !ok {
			mapX[shields[i].x] = len(mapX) + 1
		}
		if _, ok := mapY[shields[i].y]; !ok {
			mapY[shields[i].y] = len(mapY) + 1
		}
	}

	constraints := make([]Constraint, M)
	for i := 0; i < M; i++ {
		constraints[i].t = nextInt()
		constraints[i].l = nextInt()
		constraints[i].d = nextInt()
	}

	Kx := len(mapX)
	Ky := len(mapY)

	degX := make([]int, Kx+1)
	degY := make([]int, Ky+1)
	minDx := make([]int, Kx+1)
	minDy := make([]int, Ky+1)

	for i := 1; i <= Kx; i++ {
		minDx[i] = INF
	}
	for i := 1; i <= Ky; i++ {
		minDy[i] = INF
	}

	for _, p := range shields {
		degX[mapX[p.x]]++
		degY[mapY[p.y]]++
	}

	for _, c := range constraints {
		if c.t == 1 {
			if id, ok := mapX[c.l]; ok {
				if c.d < minDx[id] {
					minDx[id] = c.d
				}
			}
		} else {
			if id, ok := mapY[c.l]; ok {
				if c.d < minDy[id] {
					minDy[id] = c.d
				}
			}
		}
	}

	S := 0
	T := Kx + Ky + 1
	SS := T + 1
	TT := T + 2
	numNodes := TT + 1

	g = make([][]Edge, numNodes)
	g[S] = make([]Edge, 0, Kx+2)
	g[T] = make([]Edge, 0, Ky+2)
	for i := 1; i <= Kx; i++ {
		g[i] = make([]Edge, 0, degX[i]+2)
	}
	for j := 1; j <= Ky; j++ {
		g[Kx+j] = make([]Edge, 0, degY[j]+2)
	}
	g[SS] = make([]Edge, 0, numNodes)
	g[TT] = make([]Edge, 0, numNodes)

	level = make([]int, numNodes)
	ptr = make([]int, numNodes)
	D := make([]int, numNodes)

	addBounds := func(u, v, L, R int) {
		addEdge(u, v, R-L, -1)
		D[v] += L
		D[u] -= L
	}

	for i := 1; i <= Kx; i++ {
		diff := degX[i] - minDx[i]
		L := 0
		if diff > 0 {
			L = (diff + 1) / 2
		}
		R := (degX[i] + minDx[i]) / 2
		if R > degX[i] {
			R = degX[i]
		}
		if L > R {
			fmt.Println("-1")
			return
		}
		addBounds(S, i, L, R)
	}

	for j := 1; j <= Ky; j++ {
		diff := degY[j] - minDy[j]
		L := 0
		if diff > 0 {
			L = (diff + 1) / 2
		}
		R := (degY[j] + minDy[j]) / 2
		if R > degY[j] {
			R = degY[j]
		}
		if L > R {
			fmt.Println("-1")
			return
		}
		addBounds(Kx+j, T, L, R)
	}

	for k, p := range shields {
		u := mapX[p.x]
		v := Kx + mapY[p.y]
		addEdge(u, v, 1, k)
	}

	sumDemands := 0
	for i := 0; i < numNodes; i++ {
		if D[i] > 0 {
			addEdge(SS, i, D[i], -1)
			sumDemands += D[i]
		} else if D[i] < 0 {
			addEdge(i, TT, -D[i], -1)
		}
	}

	if r < b {
		addEdge(T, S, INF, -2)
		idxTS := len(g[T]) - 1
		idxST := len(g[S]) - 1

		dinic(SS, TT)

		tot := 0
		for _, e := range g[SS] {
			tot += e.flow
		}
		if tot != sumDemands {
			fmt.Println("-1")
			return
		}

		g[T][idxTS].cap = 0
		g[T][idxTS].flow = 0
		g[S][idxST].cap = 0
		g[S][idxST].flow = 0

		dinic(S, T)
	} else {
		dinic(SS, TT)
		addEdge(T, S, INF, -2)
		dinic(SS, TT)

		tot := 0
		for _, e := range g[SS] {
			tot += e.flow
		}
		if tot != sumDemands {
			fmt.Println("-1")
			return
		}
	}

	ans := make([]byte, N)
	redCount := 0
	for u := 1; u <= Kx; u++ {
		for _, e := range g[u] {
			if e.id >= 0 {
				if e.flow == 1 {
					ans[e.id] = 'r'
					redCount++
				} else {
					ans[e.id] = 'b'
				}
			}
		}
	}

	cost := int64(redCount)*int64(r) + int64(N-redCount)*int64(b)
	fmt.Println(cost)
	fmt.Println(string(ans))
}
```