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#F1941. Elections

    ID: 1947 传统题 2000ms 256MiB 尝试: 0 已通过: 0 难度: 7 上传者: 标签>枚举算法思想提高难度共享题库Codeforces英文题面题目来源题面语言

Elections

题目描述

C. Elections
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

You are running for a governor in a small city in Russia. You ran some polls and did some research, and for every person in the city you know whom he will vote for, and how much it will cost to bribe that person to vote for you instead of whomever he wants to vote for right now. You are curious, what is the smallest amount of money you need to spend on bribing to win the elections. To win elections you need to have strictly more votes than any other candidate.

Input

First line contains one integer n (1≤n≤105) − number of voters in the city. Each of the next n lines describes one voter and contains two integers ai and bi (0≤ai≤105;0≤bi≤104) − number of the candidate that voter is going to vote for and amount of money you need to pay him to change his mind. You are the candidate 0 (so if a voter wants to vote for you, ai is equal to zero, in which case bi will also be equal to zero).

Output

Print one integer − smallest amount of money you need to spend to win the elections.

Examples
Input
5
1 2
1 2
1 2
2 1
0 0
Output
3
Input
4
1 2
1 2
2 1
0 0
Output
2
Input
1
100000 0
Output
0

题目来源:fps-www.educg.net-codeforce-1-2833.xml.zip;FPS 共享题包,题包内第 1521 题。保留原作者与原赛事署名。