use C++ WRITE svg

To write SVG using C++, you can use a library like CairoSVG. Here is some sample code that uses CairoSVG to create an SVG file with a red circle:

#include <cairo-svg.h>

int main() {
    // Create a new SVG surface
    cairo_surface_t *surface = cairo_svg_surface_create("output.svg", 400, 400);
    cairo_t *cr = cairo_create(surface);

    // Draw a red circle
    cairo_set_source_rgb(cr, 1.0, 0.0, 0.0);
    cairo_arc(cr, 200, 200, 100, 0, 2 * M_PI);
    cairo_fill(cr);

    // Clean up
    cairo_destroy(cr);
    cairo_surface_destroy(surface);

    return 0;
}

This code creates an SVG file called "output.svg" with a 400x400 canvas and a red circle centered at (200, 200) with a radius of 100. You can modify the code to draw other shapes or add text to the SVG file.