Line Integral Over a Closed Path ABCA

%% Line integral over a closed path ABCA
% I haven't figured out a way so that the use only has to enter the vector field 'F' once so you'll just have to just copy and paste it when it asks for it again and again

syms t x y z

A = input('coordinates for A\n');
B = input('coordinates for B\n');
C = input('coordinates for C\n');

v_AB = B-A;
v_BC = C-B;
v_CA = A-C;
v_AB = t.*v_AB;
v_BC = t.*v_BC;
v_CA = t.*v_CA;

% Creates parametrized lines for the three lines
c1 =A+v_AB;
c2 =B+v_BC;
c3 =C+v_CA;

% Calculates derivative of the three lines
C1 = diff(c1,t);
C2 = diff(c2,t);
C3 = diff(c3,t);

% F(c1)
x = c1(1);
y = c1(2);
z = c1(3);
fc1 = input('Vector field\n');

% F(c2)
x = c2(1);
y = c2(2);
z = c2(3);
fc2 = input('Vector field\n');

% F(c3)
x = c3(1);
y = c3(2);
z = c3(3);
fc3 = input('Vector field\n');

% Calculates the individual integrals
a = int(dot(fc1,C1),t,0,1);
b = int(dot(fc2,C2),t,0,1);
c = int(dot(fc3,C3),t,0,1);
a+b+c