View Compilation Error

0_0_17791174_3570.cpp: In function 'void gauss_jordan(int, int)':
0_0_17791174_3570.cpp:80:7: error: redeclaration of 'int r'
   int r; for (int r = c; r < val; ++r)if (A[r][c])break;
       ^
0_0_17791174_3570.cpp:78:11: note: 'int r' previously declared here
  for (int r = equ - 1; ~r; --r)
           ^
0_0_17791174_3570.cpp:80:23: error: 'c' was not declared in this scope
   int r; for (int r = c; r < val; ++r)if (A[r][c])break;
                       ^
0_0_17791174_3570.cpp:82:39: error: 'ans' was not declared in this scope
   for (int j = r + 1; j < val; ++j)if(ans[j] == -1)ans[j] = 0;
                                       ^
0_0_17791174_3570.cpp:83:17: error: 'c' was not declared in this scope
   int k = inv[A[c][c]];
                 ^