Python は通ったが, C と Java が通らない.

76E.c

#include <stdio.h>

int main()
{
	char buf[64];
	int N;
	int i;
	int x, y;
	long sum_x=0, sum_y=0, sum_x2=0, sum_y2=0;
	int n;

	fgets(buf, sizeof(buf), stdin);
	sscanf(buf, "%d\n", &N);

	for (i = 0; i < N; i++) {
		fgets(buf, sizeof(buf), stdin);
		n = sscanf(buf, "%d %d\n", &x, &y);

		sum_x += x;
		sum_x2 += x*x;
		sum_y += y;
		sum_y2 += y*y;
	}

	printf("%ld\n", N * sum_x2 - sum_x * sum_x + N * sum_y2 - sum_y * sum_y);

	return 0;
}

76E.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

N = int(raw_input())

sum_x = 0
sum_x2 = 0
sum_y = 0
sum_y2 = 0

for i in range(N):
    x, y = (raw_input().split())
    x = int(x)
    y = int(y)
    sum_x += x
    sum_x2 += x**2
    sum_y += y
    sum_y2 += y**2

print(N * sum_x2 - sum_x**2 + N * sum_y2 - sum_y**2)

Prob76E.java

import java.io.*;
import java.math.BigInteger;

public class Prob76E {
	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int N = Integer.parseInt(br.readLine());

		BigInteger sum_x = BigInteger.ZERO;
		BigInteger sum_y = BigInteger.ZERO;
		BigInteger sum_x2 = BigInteger.ZERO;
		BigInteger sum_y2 = BigInteger.ZERO;
		for (int i = 0; i < N; i++) {
			String line = br.readLine();
			String[] nums = line.split(" +");
			BigInteger x = new BigInteger(nums[0]);
			BigInteger y = new BigInteger(nums[1]);

			sum_x = sum_x.add(x);
			sum_y = sum_y.add(y);
			sum_x2 = sum_x2.add(x.pow(2));
			sum_y2 = sum_y2.add(y.pow(2));

			System.out.println(sum_x + " " + sum_y + " " + sum_x2 + " " + sum_y2 + " ");
		}

		System.out.println(sum_x2.multiply(BigInteger.valueOf(N))
						   .subtract(sum_x.pow(2))
						   .add(sum_y2.multiply(BigInteger.valueOf(N)))
						   .subtract(sum_y.pow(2)));
	}
}