//https://leetcode.com/explore/challenge/card/30-day-leetcoding-challenge/530/week-3/3306/
public int LeftMostColumnWithOne(IBinaryMatrix binaryMatrix)
{
var dimensions = binaryMatrix.Dimensions();
var min = int.MaxValue;
for (int row = 0; row < dimensions[0]; row++)
{
var low = 0;
var high = dimensions[1] - 1;
while (low <= high)
{
var mid = (low + high) / 2;
if (binaryMatrix.Get(row, mid) == 1)
{
if (mid == 0)
{
return(0); // we're done completely. Cant get lower than zero.
}
else if (binaryMatrix.Get(row, mid - 1) == 0)
{
min = Math.Min(min, mid);
break; //move to next row
}
else
{
high = mid - 1;
}
}
else
{
low = mid + 1;
}
}
}
return((min < int.MaxValue) ? min : -1);
}
private int find(int x, int y, int rows, int minIndex, IBinaryMatrix binaryMatrix)
{
var val = binaryMatrix.Get(x, y);
if (val == 0)
{
x++;
}
else
{
minIndex = y;
y--;
}
if (x < rows && y >= 0)
{
minIndex = find(x, y, rows, minIndex, binaryMatrix);
}
return(minIndex);
}