/in/foo.cc: In function 'int main()':
/in/foo.cc:26:9: warning: operation on 'ji1' may be undefined [-Wsequence-point]
    ans1[++ji1]=abs(a[ji1]-b[n-ji1+1]);
         ^~~~~
/in/foo.cc:26:9: warning: operation on 'ji1' may be undefined [-Wsequence-point]
/in/foo.cc:30:9: warning: operation on 'ji2' may be undefined [-Wsequence-point]
    ans2[++ji2]=abs(b[ji2]-a[n-ji2+1]);
         ^~~~~
/in/foo.cc:30:9: warning: operation on 'ji2' may be undefined [-Wsequence-point]