Sequence in Matrix

let sizeOfMatrix = gets().split(' ').map(Number);
let row = sizeOfMatrix[0];
let col = sizeOfMatrix[1];
let matrix = [];


for(let i = 0;i < row;i ++){
    let current = gets().split(' ');
    matrix[i] = [];
    for(let j = 0; j < col;j ++){
        matrix[i].push(current[j]);
    }
}


if(row == 0 || col == 0){
    lineResult = 0;
    columnResult = 0;
    firstDiagonal = 0;
    secondDiagonal = 0;

}
console.table(matrix);
//check line.
let lineResult = 1;
for(let i = 0;i <= row - 1;i ++){
    let line = 1;
    for(let j = 0;j < col - 1;j ++){
        if(matrix[i][j] === matrix[i][j + 1]){
            line ++;
            if(line > lineResult){
                lineResult = line ;
            }
        }
        else{
            line = 1;
        }
    }
}
//check column.
let columnResult = 1;
for(let i = 0;i <= row - 1;i ++){
    let column = 1;
    for(let j = 0;j < col - 1; j ++){
        if(matrix[j][i] === matrix[j + 1][i]){
            column ++;
            if(column > columnResult){
                columnResult = column;
            }
        }
        else{
            column = 1;
        }
    }
}
//check first diagonal.
let firstDiagonal = 1;
for(let i = 0;i < row - 1;i++){
    let diagonal1 = 1;
    for(let j = 0;j < col - 1;j ++){
        if(matrix[i][j] === matrix[i + 1][j + 1]){
            diagonal1 ++;
            if(diagonal1 > firstDiagonal){
                firstDiagonal  = diagonal1;
            }
        }
        else{
            diagonal1 = 1;
        }
        i ++;
    }
}

//check second diagonal.
let secondDiagonal = 1;
for(let i = 0;i < row - 1;i++){
    let diagonal2 = 1;
    for(let j = col - 1;j >= 1;j--){
        if(matrix[i][j] === matrix[i + 1][j - 1]){
            diagonal2 ++;
            if(diagonal2 > secondDiagonal){
                secondDiagonal = diagonal2;
            }
        }
        else{
            diagonal2 = 1;
        }
        i++;
    }
}


print(Math.max(lineResult,columnResult,firstDiagonal,secondDiagonal));