<pre>
#include <iostream>
#include <vector>
long largestProduct(std::vector<std::vector<int> >arr)
{
std::vector<long>products;
for(int row=0; row<20; row++)
{
for(int col=0; col<20; col++)
{
int left=col-4;
int right=col+4;
int down=row+4;
int up=row-4;
while(up<0)
{
up++;
}
while(down>20)
{
down--;
}
if(down-up>=4)
{
for(up; up<=down-4; up++)
{
long product=1;
int rowCount=up;
int rowDist=rowCount+4;
for(rowCount; rowCount<rowDist; rowCount++)
{
product=product*arr[rowCount][col];
}
products.push_back(product);
}
}
while(left<0)
{
left++;
}
while(right>20)
{
right--;
}
if(right-left>=4)
{
for(left; left<=right-4; left++)
{
long product=1;
int colCount=left;
int colDist=colCount+4;
for(colCount; colCount<colDist; colCount++)
{
product=product*arr[row][colCount];
}
products.push_back(product);
}
}
down=row+4;
up=row-4;
left=col-4;
right=col+4;
while(down>20)
{
down--;
}
while(up<0)
{
up++;
}
while(left<0)
{
left++;
}
while(right>20)
{
right--;
}
if(down-up>=4 && right-left>=4)
{
for(up; up<=down-4; up++)
{
for(left; left<=right-4; left++)
{
int rowCount=left;
int rowDist=rowCount+4;
int colCount=left;
int colDist=colCount+4;
while(rowCount<rowDist)
{
long product=1;
while(colCount<colDist)
{
product=product*arr[rowCount][colCount];
rowCount=rowCount+1;
colCount=colCount+1;
}
products.push_back(product);
}
}
}
}
}
}
long MAX=0;
for(int i=0; i<products.size(); i++)
{
if(products[i]>MAX)
{
MAX=products[i];
}
}
return MAX;
}
int main()
{
std::vector< std::vector<int> >arr{
{8, 2, 22, 97, 38, 15, 0, 40, 0, 75, 4, 5, 7, 78, 52, 12, 50, 77, 91, 8},
{49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 4, 56, 62, 0},
{81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 3, 49, 13, 36, 65},
{52, 70, 95, 23, 4, 60, 11, 42, 69, 24, 68, 56, 1, 32, 56, 71, 37, 2, 36, 91},
{22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80},
{24, 47, 32, 60, 99, 3, 45, 2, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50},
{32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70},
{67, 26, 20, 68, 2, 62, 12, 20, 95, 63, 94, 39, 63, 8, 40, 91, 66, 49, 94, 21},
{24, 55, 58, 5, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88, 34, 89, 63, 72},
{21, 36, 23, 9, 75, 0, 76, 44, 20, 45, 35, 14, 0, 61, 33, 97, 34, 31, 33, 95},
{78, 17, 53, 28, 22, 75, 31, 67, 15, 94, 3, 80, 4, 62, 16, 14, 9, 53, 56, 92},
{16, 39, 5, 42, 96, 35, 31, 47, 55, 58, 88, 24, 0, 17, 54, 24, 36, 29, 85, 57},
{86, 56, 0, 48, 35, 71, 89, 7, 5, 44, 44, 37, 44, 60, 21, 58, 51, 54, 17, 58},
{19, 80, 81, 68, 5, 94, 47, 69, 28, 73, 92, 13, 86, 52, 17, 77, 4, 89, 55, 40},
{ 4, 52, 8, 83, 97, 35, 99, 16, 7, 97, 57, 32, 16, 26, 26, 79, 33, 27, 98, 66},
{88, 36, 68, 87, 57, 62, 20, 72, 3, 46, 33, 67, 46, 55, 12, 32, 63, 93, 53, 69},
{ 4, 42, 16, 73, 38, 25, 39, 11, 24, 94, 72, 18, 8, 46, 29, 32, 40, 62, 76, 36},
{20, 69, 36, 41, 72, 30, 23, 88, 34, 62, 99, 69, 82, 67, 59, 85, 74, 4, 36, 16},
{20, 73, 35, 29, 78, 31, 90, 1, 74, 31, 49, 71, 48, 86, 81, 16, 23, 57, 5, 54},
{ 1, 70, 54, 71, 83, 51, 54, 69, 16, 92, 33, 48, 61, 43, 52, 1, 89, 19, 67, 48}
};
std::cout<<largestProduct(arr);
}
What I have tried:
I have tried by debugging but it gets complicated, I know that there are some values that count more than once but I will solve it, now my main problem is I want to understand what goes wrong