Contents

1029. Two City Scheduling

Problem

There are 2N people a company is planning to interview. The cost of flying the i-th person to city A is costs[i][0], and the cost of flying the i-th person to city B is costs[i][1].

Return the minimum cost to fly every person to a city such that exactly N people arrive in each city.

example 1

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Input: [[10,20],[30,200],[400,50],[30,20]]
Output: 110
Explanation: 
The first person goes to city A for a cost of 10.
The second person goes to city A for a cost of 30.
The third person goes to city B for a cost of 50.
The fourth person goes to city B for a cost of 20.

The total minimum cost is 10 + 30 + 50 + 20 = 110 to have half the people interviewing in each city.

Constraint

  • 1 <= len(costs) <= 100
  • It is guaranteed that len(costs) is even.
  • 1 <= costs[i][0], costs[i][1] <= 1000

Solution

Linked list

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func twoCitySchedCost(costs [][]int) int {
    st:= list{Val:-1}
    
    for idx := range costs {
        st.add(costs[idx][0],costs[idx][1], idx)
    }
    
    s:= 0
    i:=0
    stt := &st
    
    
    for stt != nil {
        i++
        if i<=len(costs)/2{
            s+=costs[stt.Idx][0]
        } else {
            s+=costs[stt.Idx][1]
        }
        stt = stt.Next
        
    }

    return s
}

type list struct {
    Next *list
    Val int
    Idx int
}

func (v *list) add(vala, valb, idx int) {
    if v.Val == -1 {
        v.Val=vala-valb
        v.Idx = idx
        
        return
    }
    
    val := vala-valb
    

    for v != nil {
        if val <= v.Val {
            ppp := *v
            *v = list{
                Val: val,
                Idx:idx,
                Next: &ppp,
            }
            return
        }
        if v.Next == nil && val > v.Val{
            v.Next = &list{
                Val: val,
                Idx:idx,
            }
            return
        }
        v = v.Next
    }
    
}

func (v *list) print(){
    for v!= nil{
        fmt.Println(v)
        v = v.Next
    }
}