View Compilation Error

0_0_36480835_14883.cpp: In function 'int main()':
0_0_36480835_14883.cpp:56:41: error: lvalue required as left operand of assignment
             B.mp[1][1] = B.mp[1][2] = 1 = B.mp[2][3] = B.mp[3][1] = B.mp[3][4];
                                         ^
0_0_36480835_14883.cpp:57:30: error: 'struct mat' has no member named 'p'
             B.mp[2][1] = 5,B.p[4][1] = -1;
                              ^