function [PR_wu, PR_pc] = func_opt_3RISs_wu(HT,HR,H21,H32,typeRIS,NG)

[N, NT] = size(HT);

NR = size(HR,1);

T2 = -eye(N);

T3 = -eye(N);

PR_loop = zeros(1,1e3);

for iIter = 1:1e3

% Optimize T1

HR1 = HR*T3*H32*T2*H21;

HT1 = HT;

[~, T1] = func_opt_RIS_MIMO(zeros(NR,NT),HR1,HT1,typeRIS,NG);

% Optimize T2

HR2 = HR*T3*H32;

HT2 = H21*T1*HT;

[~, T2] = func_opt_RIS_MIMO(zeros(NR,NT),HR2,HT2,typeRIS,NG);

% Optimize T3

HR3 = HR;

HT3 = H32*T2*H21*T1*HT;

[~, T3] = func_opt_RIS_MIMO(zeros(NR,NT),HR3,HT3,typeRIS,NG);

% Compute PR at this iteration

PR_loop(iIter+1) = norm(HR*T3*H32*T2*H21*T1*HT) ^ 2;

% Stopping condition

if (PR_loop(iIter+1) - PR_loop(iIter))/PR_loop(iIter) < 1e-3

%iIter

break;

end

PR_wu = PR_loop(iIter+1);

PR_pc = norm(HR*(T3-eye(N))*H32*(T2-eye(N))*H21*(T1-eye(N))*HT) ^ 2;