Leetcode: Spiral Matrix in C++

Given a matrix of m x n elements (m rows, n columns), return all elements of the matrix in spiral order.

For example,

Given the following matrix:
[
[ 1, 2, 3 ],
[ 4, 5, 6 ],
[ 7, 8, 9 ]
]

You should return [1,2,3,6,9,8,7,4,5].

Solution:
void spiral_input(vector<vector<int>> s,int lx,int ly,int m,int n, vector<int>& result)
    {
    if(m<=0||n<=0)
return;
for(int i=0;i<n;i++)
result.push_back(s[lx][ly+i]);
for(int i=1;i<m;i++)
result.push_back(s[lx+i][ly+n-1]);
    if(m!=1)
    {
        for(int i=n-2;i>=0;i--)
    result.push_back(s[lx+m-1][ly+i]);
    }
if(n!=1)
    {
        for(int i=m-2;i>=1;i--)
    result.push_back(s[lx+i][ly]);
    }
spiral_input(s,lx+1,ly+1,m-2,n-2, result);
    }
    vector<int> spiralOrder(vector<vector<int> > &matrix) {
        vector<int> result;
        if(matrix.size()==0)
        return result;
        spiral_input(matrix,0,0,matrix.size(),matrix[0].size(),result);
        
    }