| # 1311_F. Moving Points |
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| ## Problem Description |
| There are n points on a coordinate axis OX. The i-th point is located at the integer point x_i and has a speed v_i. It is guaranteed that no two points occupy the same coordinate. All n points move with the constant speed, the coordinate of the i-th point at the moment t (t can be non-integer) is calculated as x_i + t β
v_i. |
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| Consider two points i and j. Let d(i, j) be the minimum possible distance between these two points over any possible moments of time (even non-integer). It means that if two points i and j coincide at some moment, the value d(i, j) will be 0. |
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| Your task is to calculate the value β_{1 β€ i < j β€ n} d(i, j) (the sum of minimum distances over all pairs of points). |
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| Input |
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| The first line of the input contains one integer n (2 β€ n β€ 2 β
10^5) β the number of points. |
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| The second line of the input contains n integers x_1, x_2, ..., x_n (1 β€ x_i β€ 10^8), where x_i is the initial coordinate of the i-th point. It is guaranteed that all x_i are distinct. |
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| The third line of the input contains n integers v_1, v_2, ..., v_n (-10^8 β€ v_i β€ 10^8), where v_i is the speed of the i-th point. |
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| Output |
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| Print one integer β the value β_{1 β€ i < j β€ n} d(i, j) (the sum of minimum distances over all pairs of points). |
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| Examples |
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| Input |
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| 3 |
| 1 3 2 |
| -100 2 3 |
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| Output |
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| 3 |
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| Input |
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| 5 |
| 2 1 4 3 5 |
| 2 2 2 3 4 |
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| Output |
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| 19 |
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| Input |
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| 2 |
| 2 1 |
| -3 0 |
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| Output |
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| 0 |
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| ## Contest Information |
| - **Contest ID**: 1311 |
| - **Problem Index**: F |
| - **Points**: 0.0 |
| - **Rating**: 1900 |
| - **Tags**: data structures, divide and conquer, implementation, sortings |
| - **Time Limit**: {'seconds': 2, 'nanos': 0} seconds |
| - **Memory Limit**: 256000000 bytes |
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| ## Task |
| Solve this competitive programming problem. Provide a complete solution that handles all the given constraints and edge cases. |