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//ac #include #include using namespace std; double x[10010], y[10010]; double x_1[10010], y_1[10010]; double sx, sy; int n; int main() { scanf("%d", &n); sx = sy = 0; for (int i = 0; i < n; ++i) { scanf("%lf %lf", &x[i], &y[i]); if (i % 2 == 0) sx += x[i], sy += y[i]; else sx -= x[i], sy -= y[i]; } if (n % 2 == 0 && (sx != 0 || sy != 0)) { printf("NO\n"); return 0; } if (n % 2 == 1) { x_1[0] = sx, y_1[0] = sy; } else { x_1[0] = y_1[0] = 0; } for (int i = 1; i < n; ++i) { x_1[i] = 2 * x[i - 1] - x_1[i - 1]; y_1[i] = 2 * y[i - 1] - y_1[i - 1]; } printf("YES\n"); for (int i = 0; i < n; ++i) { printf("%.3lf %.3lf\n", x_1[i], y_1[i]); } return 0; }