C++ Find the minimum value in every row of a n*m matrix

Question

How can I find the minimum value in every row of a n*m matrix, and put these values to a new array? I have this code so far, but it's not working properly:

void min(const int t[max_city][max_bird], int allmin[], int n, int m)
{
    int min=t[0][0];
    for(int i=0; i<n; ++i)
    {
        for(int j=0; j<m; ++j)
        {
            if(t[i][j]<min)
            {
                min=t[i][j];
            }
        }
        allmin[i]=min;
        cout << i+1 << ". min: " << allmin[i] << endl;
    }
}

Answer 1

Declare min inside the first loop, and initialize it there:

for(int i=0; i<n; ++i)
{
   int min= INT_MAX; //do this here so that it gets initialized each time!

   for(int j=0; j<m; ++j)
   {
      //your code
   }
   //etc
}

To use INT_MAX, include <climits>.

---

Using std::min_element, your function can be re-written as:

void min(const int t[max_city][max_bird], int allmin[], int n, int m)
{
    for(int i=0; i<n; ++i)
    {
        allmin[i] = *std::min_element(t[i], t[i] + m);
    }
}

It became so short!

The function std::min_element returns the pointer to the minimum element, so you dereference the returned pointer to get the value (of the minimum element).

To use std::min_element in your program, you have to include this header:

#include <algorithm>

Hope that helps.