B"Annie has gotten bored of winning every coding contest and farming unlimited rating. Today, she is going to farm potatoes instead. Annie's garden is an infinite 2D plane. She has n potatoes to plant, and the i -th potato must be planted at (x_i,y_i) . Starting at the point (0, 0) , Annie begins walking, in one step she can travel one unit right or up (increasing her x or y coordinate by 1 respectively). At any point (X,Y) during her walk she can plant some potatoes at arbitrary points using her potato gun, consuming max(|X-x|,|Y-y|) units of energy in order to plant a potato at (x,y) . Find the minimum total energy required to plant every potato. Note that Annie may plant any number of potatoes from any point. The first line contains the integer n ( 1 <= n <= 800 ,000 ). The next n lines contain two integers x_i and y_i ( 0 <= x_i,y_i <= 10^9 ), representing the location of the i -th potato. It is possible that some potatoes should be planted in the same location. Print the minimum total energy to plant all potatoes. In example 1 , Annie can travel to each spot directly and plant a potato with no energy required. In example 2 , moving to (1,0) , Annie plants the second potato using 1 energy. Next, she travels to (1,1) and plants the first potato with 0 energy. "...