How to find a minimum and maximum value in a 2D array ROW?

I have a program that generates 10 rows and 5 columns and the user inputs data. My question is, how can I find the maximum and lowest values in each row? I have been working on this for a good hour but cannot figure this out. I have attempted to solve this many times; here is my current code.

#include <iostream>
#include <iomanip>
using namespace std;

int returnMax(int[][]);
int main() 
{
    double sales[10][5];
    string name[10];
    double highest;
    double lowest;
    double avg;
    // Populating table
    for (int row = 0; row < 1; row++) 
    {
        cout << "Enter the salesman's name: " << endl;
        cin >> name[row];
        cout << "Enter the amount of sales for the five years" << endl;
        for (int col = 0; col < 5; col++) {
            cin >> sales[row][col];
        }
    }
    cout << returnMax(sales[1][0]) << endl;
    return 0;
}

int returnMax(int a[][]) 
{
    int max;
    for (int i = 0; i < 1; i++) {
        max = a[i][0];
        for (int j = 0; j < 5; j++) {
            if (a[i][j] > max)
                max = a[i][j];
        }
    }
    return max;
}