B. Cover Pointstime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard outputThere are n points on the plane, (x_1,y_1), (x_2,y_2), \ldots, (x_n,y_n).You need to place an isosceles triangle with two sides on the coordinate axis to cover all points (a point is covered if it lies inside the triangle or on the side of the triangle). Calculate the minimum length of the shorter side of the triangle.InputFirst line contains one integer n (1 \leq n \leq 10^5).Each of the next n lines contains two integers x_i and y_i (1 \leq x_i,y_i \leq 10^9).OutputPrint the minimum length of the shorter side of the triangle. It can be proved that it's always an integer.ExamplesInput31 11 22 1Output3Input41 11 22 12 2Output4NoteIllustration for the first example: Illustration for the second example: 
Input31 11 22 1
Output3
['geometry', 'math', '*900']