def drawPins(input_data, xpins, ypins, map):
    """
    Draw pins on input_data
    
    Inputs:
       - input_data: np.array of size (C, H, W) (all zeros to start with)
       - xpins & ypins: np.array of x-coordinates and y-coordinates for all pins
                    e.g., [x1, x2 ... xm] and [y1, y2, ... ym] for m pins
       - map: layout layer map (dictionary from layer name to index)
                    
    Outputs:
       - output_data: np.array of size (C, H, W) (with pixels corresponding to pins in layer 'pins' set to '1')
    """
    
    output_data = input_data
    
    for (x, y) in zip(xpins, ypins):
        output_data[map['pin'], y, x] = 1
    
    return output_data