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 你忘了关闭minCutChan因此main已经进入范围并且所有go例程都已完成。 
 
 sync.WaitGroup使用频道，您可以使用sync.WaitGroup 
 
 编辑 ：要处理totalCount我会使用atomic.AddInt64看到新的更新示例： 
 
 请参阅这些编辑的工作模拟示例： http ： //play.golang.org/p/WyCQrWK5aa 
 
package main

import (
    "fmt"
    "sync"
    "sync/atomic"
)

type Graph struct {
}

func contractGraph(Graph) int { return 0 }

func worker(wg *sync.WaitGroup, graph Graph, i int, minCutChan chan<- int) {
    defer wg.Done()
    for {
        count := atomic.AddInt64(&totalCount, -1) 
        if count < 0 {
            break
        }
        fmt.Println("Worker Iteration", count)
        min_cut := contractGraph(graph)
        minCutChan <- min_cut
    }
}

func workerRunner(graph Graph, minCutChan chan int, workerCount int) {
    wg := new(sync.WaitGroup)
    wg.Add(workerCount)
    for i := 0; i < workerCount; i++ {
        go worker(wg, graph, i, minCutChan)
    }
    wg.Wait()
    close(minCutChan)
}

var totalCount int64

func main() {
    workerCount := 4
    graph := Graph{}
    totalCount = 100
    minCutChan := make(chan int, workerCount+1)
    go workerRunner(graph, minCutChan, workerCount)

    go func() {
    }()

    // read the resulting min cuts
    minCut := 0
    for _minCut := range minCutChan {
        if minCut == 0 || _minCut < minCut {
            minCut = _minCut
        }
    }
    fmt.Println(minCut)
}
 
 更进一步的风格是在匿名函数中旋转工作者： 
 
 http://play.golang.org/p/nT0uUutQyS 
 
 包主 
 
import (
    "fmt"
    "sync"
    "sync/atomic"
)

type Graph struct {
}

func contractGraph(Graph) int { return 0 }

var totalCount int64

func workerRunner(graph Graph, minCutChan chan int, workerCount int) {
    var wg sync.WaitGroup
    wg.Add(workerCount)
    for i := 0; i < workerCount; i++ {
        go func() {
            defer wg.Done()
            for {
                count := atomic.AddInt64(&totalCount, -1)
                if count < 0 {
                    break
                }
                fmt.Println("Worker Iteration", count)

                min_cut := contractGraph(graph)
                minCutChan <- min_cut
            }
        }()
    }
    wg.Wait()
    close(minCutChan)
}

func main() {
    workerCount := 4
    totalCount = 100
    graph := Graph{}
    minCutChan := make(chan int, workerCount+1)
    go workerRunner(graph, minCutChan, workerCount)

    // read the resulting min cuts
    minCut := 0
    for _minCut := range minCutChan {
        if minCut == 0 || _minCut < minCut {
            minCut = _minCut
        }
    }
    fmt.Println(minCut)
}

You forgot to close the minCutChan so main is stuck into range and all the go routines have completed.
 
to not use the channel you can use sync.WaitGroup
 
EDIT: To handle the totalCount I would use atomic.AddInt64 see the new updated examples:
 
see a working mock example with these edits: http://play.golang.org/p/WyCQrWK5aa
 
package main

import (
    "fmt"
    "sync"
    "sync/atomic"
)

type Graph struct {
}

func contractGraph(Graph) int { return 0 }

func worker(wg *sync.WaitGroup, graph Graph, i int, minCutChan chan<- int) {
    defer wg.Done()
    for {
        count := atomic.AddInt64(&totalCount, -1) 
        if count < 0 {
            break
        }
        fmt.Println("Worker Iteration", count)
        min_cut := contractGraph(graph)
        minCutChan <- min_cut
    }
}

func workerRunner(graph Graph, minCutChan chan int, workerCount int) {
    wg := new(sync.WaitGroup)
    wg.Add(workerCount)
    for i := 0; i < workerCount; i++ {
        go worker(wg, graph, i, minCutChan)
    }
    wg.Wait()
    close(minCutChan)
}

var totalCount int64

func main() {
    workerCount := 4
    graph := Graph{}
    totalCount = 100
    minCutChan := make(chan int, workerCount+1)
    go workerRunner(graph, minCutChan, workerCount)

    go func() {
    }()

    // read the resulting min cuts
    minCut := 0
    for _minCut := range minCutChan {
        if minCut == 0 || _minCut < minCut {
            minCut = _minCut
        }
    }
    fmt.Println(minCut)
}
 
even more in go style is to spin the workers inside an anonymous function: 
 
http://play.golang.org/p/nT0uUutQyS
 
package main
 
import (
    "fmt"
    "sync"
    "sync/atomic"
)

type Graph struct {
}

func contractGraph(Graph) int { return 0 }

var totalCount int64

func workerRunner(graph Graph, minCutChan chan int, workerCount int) {
    var wg sync.WaitGroup
    wg.Add(workerCount)
    for i := 0; i < workerCount; i++ {
        go func() {
            defer wg.Done()
            for {
                count := atomic.AddInt64(&totalCount, -1)
                if count < 0 {
                    break
                }
                fmt.Println("Worker Iteration", count)

                min_cut := contractGraph(graph)
                minCutChan <- min_cut
            }
        }()
    }
    wg.Wait()
    close(minCutChan)
}

func main() {
    workerCount := 4
    totalCount = 100
    graph := Graph{}
    minCutChan := make(chan int, workerCount+1)
    go workerRunner(graph, minCutChan, workerCount)

    // read the resulting min cuts
    minCut := 0
    for _minCut := range minCutChan {
        if minCut == 0 || _minCut < minCut {
            minCut = _minCut
        }
    }
    fmt.Println(minCut)
}