# Fixing the editorial solution for Maximum Area of Triangle!

#1
``````const int maxn=1009;
const int maxc=3;
int l[maxc];
int rgt[maxc];
int top[maxc][maxn];
int bottom[maxc][maxn];
int mapcolor(char c)
{
if (c == 'r')
return 0;
else if (c == 'g')
return 1;
else if (c == 'b')
return 2;
}
double findarea(int r,int c)
{
double ans = (double)1;

// for each column
for (int i = 0; i < c; i++)

// for each top vertex
for (int x = 0; x < 3; x++)

// for each bottom vertex
for (int y = 0; y < 3; y++)
{
// finding the third color of
// vertex either on rgt or l.
int z = 3 - x - y;

// finding area of triangle on l side of column.
if (x != y && top[x][i] != 1000000 && bottom[y][i] != -1 && l[z] != 1000000)
{
ans = max(ans, ((double)1/(double)2) *
(bottom[y][i] - top[x][i] + 1) *
(i - l[z] + 1));
}

// finding area of triangle on rgt side of column.
if (x != y && top[x][i] != 1000000 &&
bottom[y][i] != -1 &&
rgt[z] != -1)
{
//  if(x==0 && y==2)cout<<bottom[y][i]<<" "<<top[x][i]<<" "<<rgt[z]<<endl;
ans = max(ans, ((double)1/(double)2) *
(bottom[y][i] - top[x][i] + 1) *
(rgt[z] - i + 1));
}
}

return ans;
}
// Precompute the vertices of top, bottom, l
// and rgt and then computing the maximum area.
double maxarea(vector<string>& mat,int r, int c)
{
for(int i=0;i<3;i++)
{
l[i]=1000000;
rgt[i]=-1;
for(int j=0;j<c;j++)
{
top[i][j]=1000000;
bottom[i][j]=-1;
}
}

// finding the r, b, g cells for the l
// and rgt vertices.
for (int i = 0; i < r; i++)
{
for (int j = 0; j < c; j++)
{
l[mapcolor(mat[i][j])] =
min(l[mapcolor(mat[i][j])], j);
rgt[mapcolor(mat[i][j])] =
max(l[mapcolor(mat[i][j])], j);
}
}
// finding set of {r, g, b} of top and
// bottom for each column.
for (int j = 0; j < c; j++)
{
for( int i = 0; i < r; i++)
{
top[mapcolor(mat[i][j])][j] =
min(top[mapcolor(mat[i][j])][j], i);
bottom[mapcolor(mat[i][j])][j] =
max(bottom[mapcolor(mat[i][j])][j], i);
}
}
return findarea(r,c);
}
int Solution::solve(vector<string> &A) {
if(A[0]==A[1] && A[1]==A[2])
return 0;
double res=maxarea(A,A.size(),A[0].size());
return ceil(res);
}

``````

#2

If you guys have any doubt about testcases or soln check this out…it will surely help you guys

#3

Thanks @bugs_bunny , guys just paste his solution , code is fixed acc to test cases and it works.