foo.cc: In function 'int main()':
foo.cc:13:25: error: 'c' was not declared in this scope
   13 |                         c[i][j]+=a[i][j];
      |                         ^
foo.cc:15:25: error: 'c' was not declared in this scope
   15 |                         c[j][1]=a[j][1];
      |                         ^
foo.cc:18:9: error: expected primary-expression before '}' token
   18 |         }
      |         ^

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