#include <stdio.h>

void chmax(long long *a, long long b)
{
	if (*a < b) *a = b;
}

int main()
{
	int i, N, A[5001][3];
	scanf("%d", &N);
	for (i = 1; i <= N; i++) scanf("%d %d %d", &(A[i][0]), &(A[i][1]), &(A[i][2]));
	
	int j, cur, prev;
	long long dp[2][3] = {}, tmp[3];
	for (i = 1, cur = 1, prev = 0; i <= N; i++, cur ^= 1, prev ^= 1) {
		dp[cur][0] = 0;
		dp[cur][1] = 0;
		dp[cur][2] = 0;
		for (j = i, tmp[0] = 0, tmp[1] = 0, tmp[2] = 0; j <= N; j++) {
			tmp[0] += A[i][0]--;
			tmp[1] += A[i][1]--;
			tmp[2] += A[i][2]--;
			if (A[i][0] < 0) A[i][0] = 0;
			if (A[i][1] < 0) A[i][1] = 0;
			if (A[i][2] < 0) A[i][2] = 0;
		}
		chmax(&(dp[cur][0]), dp[prev][1] + tmp[0]);
		chmax(&(dp[cur][0]), dp[prev][2] + tmp[0]);
		chmax(&(dp[cur][1]), dp[prev][0] + tmp[1]);
		chmax(&(dp[cur][1]), dp[prev][2] + tmp[1]);
		chmax(&(dp[cur][2]), dp[prev][0] + tmp[2]);
		chmax(&(dp[cur][2]), dp[prev][1] + tmp[2]);
	}
	
	long long ans = 0;
	for (i = 0; i < 3; i++) chmax(&ans, dp[prev][i]);
	printf("%lld\n", ans);
	fflush(stdout);
	return 0;
}