/in/foo.cc: In function 'int main()':
/in/foo.cc:7:17: error: 'strlen' was not declared in this scope
  int l1=strlen(a),l2=strlen(b),i,temp=0,x;
                 ^
/in/foo.cc:8:6: error: 'i' was not declared in this scope
  for(i=0;i<l1;i++)
      ^
/in/foo.cc:11:6: error: 'i' was not declared in this scope
  for(i=0;i<l2;i++)
      ^
/in/foo.cc:11:12: error: 'l2' was not declared in this scope
  for(i=0;i<l2;i++)
            ^~
/in/foo.cc:13:4: error: 'l2' was not declared in this scope
  d[l2]=0;
    ^~
/in/foo.cc:14:6: error: 'i' was not declared in this scope
  for(i=l1+1;i<50;i++)
      ^
/in/foo.cc:16:6: error: 'i' was not declared in this scope
  for(i=l2+1;i<50;i++)
      ^
/in/foo.cc:20:7: error: 'i' was not declared in this scope
   for(i=0;i<=l1;i++)
       ^
/in/foo.cc:22:4: error: 'x' was not declared in this scope
    x=c[i]+d[i]+temp;
    ^
/in/foo.cc:22:16: error: 'temp' was not declared in this scope
    x=c[i]+d[i]+temp;
                ^~~~
/in/foo.cc:27:8: error: 'i' was not declared in this scope
    for(i=l1-1;i>=0;i--)
        ^
/in/foo.cc:30:8: error: 'i' was not declared in this scope
    for(i=l1;i>=0;i--)
        ^
/in/foo.cc:35:7: error: 'i' was not declared in this scope
   for(i=0;i<=l2;i++)
       ^
/in/foo.cc:37:4: error: 'x' was not declared in this scope
    x=c[i]+d[i]+temp;
    ^
/in/foo.cc:37:16: error: 'temp' was not declared in this scope
    x=c[i]+d[i]+temp;
                ^~~~
/in/foo.cc:42:8: error: 'i' was not declared in this scope
    for(i=l2-1;i>=0;i--)
        ^
/in/foo.cc:45:8: error: 'i' was not declared in this scope
    for(i=l2;i>=0;i--)
        ^