移植Euler 8号项目

Question

I am trying to learn Go, and I decided to use Project Euler to help me. I have previously solved some of the problems in Javascript. I am trying to port #8 to Go.

Here it is in Javascript

var n = "7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450";

// Split our input into an array
n = n.split("");

// Loop through every 13 length chuck multiplying them. Keep track of the largest
var largest = 0;
for (var i = 0; i < (n.length - 12); i++) {
    var b = n.slice(i, i + 13);
    var product = b.reduce(function(prev, current) {
        return prev * Number(current);
    }, 1);
    if (product > largest) {
        largest = product;
    }
}
console.log(largest);

And here is my port in Go

import (
    "fmt"
    "strconv"
    "strings"
)

var data string = "7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450"

func main() {
    // Get an array of ints
    var grid []int
    var stringGrid []string = strings.Split(data, "")
    for i := 0; i < 1000; i++ {
        cell, _ := strconv.Atoi(stringGrid[i])
        grid = append(grid, cell)
    }

    // Find the largest one
    largest := 0
    for i := 0; i < len(grid)-12; i++ {
        a := grid[i : i+13]
        total := 1
        for b := 0; b < len(a); b++ {
            total *= a[b]
        }
        if total > largest {
            largest = total
        }
    }
    fmt.Println(largest)
}

I can't find out what is wrong, if I add a bunch of prints to both of them, the spit out the same sequences of numbers, but the Go one doesn't seem to be doing the multiplication right?!? I double checked by hand. There must be some small thing I am missing?