View Compilation Error

0_0_17181332_18403.cpp: In function 'int main()':
0_0_17181332_18403.cpp:10:19: error: lvalue required as left operand of assignment
    else if((a=1&&b=n)||(a=n&&b=1)) c=0;
                   ^
0_0_17181332_18403.cpp:10:31: error: lvalue required as left operand of assignment
    else if((a=1&&b=n)||(a=n&&b=1)) c=0;
                               ^
0_0_17181332_18403.cpp:12:22: error: lvalue required as left operand of assignment
    else if(a+1=b||b+1=a) c=1;
                      ^