// yukicoder: No.497 入れ子の箱 // 2019.7.14 bal4u #include #include #if 1 #define gc() getchar_unlocked() #else #define gc() getchar() #endif int in() { // 非負整数の入力 int n = 0, c = gc(); do n = 10 * n + (c & 0xf); while ((c = gc()) >= '0'); return n; } #define MAX 1005 typedef struct { int x, y, z; } T; T a[MAX+5]; int N; int dp[MAX+5]; int cmp(const void *a, const void *b) { int t; t = ((T *)a)->x - ((T *)b)->x; if (t) return t; t = ((T *)a)->y - ((T *)b)->y; if (t) return t; return ((T *)a)->z - ((T *)b)->z; } int main() { int i, j, ans; N = in(); for (i = 0; i < N; i++) { int t, x = in(), y = in(), z = in(); if (x > y) t = x, x = y, y = t; if (y > z) { t = y, y = z, z = t; if (x > y) t = x, x = y, y = t; } a[i].x = x, a[i].y = y, a[i].z = z; } qsort(a, N, sizeof(T), cmp); if (a[0].x == a[N-1].x) ans = 1; else { for (i = 0; i < N; i++) for (j = 0; j < i; j++) { if (a[i].x > a[j].x && a[i].y > a[j].y && a[i].z > a[j].z) if (dp[j]+1 > dp[i]) dp[i] = dp[j]+1; } ans = 0; for (i = 0; i < N; i++) if (dp[i] > ans) ans = dp[i]; } printf("%d\n", ans+1); return 0; }