almost_magic_square() {
    local -n _a="$1"
    local -n _out="$2"
    local -a _rowSum=(0 0 0) _colSum=(0 0 0)
    local -a _m
    local _i _j
    for ((_i = 0; _i < 3; _i++)); do
        for ((_j = 0; _j < 3; _j++)); do
            _m[_i*3+_j]=${_a[_i*3+_j]}
        done
    done
    for ((_i = 0; _i < 3; _i++)); do
        for ((_j = 0; _j < 3; _j++)); do
            _rowSum[_i]=$(( _rowSum[_i] + _m[_i*3+_j] ))
            _colSum[_i]=$(( _colSum[_i] + _m[_j*3+_i] ))
        done
    done
    local _maxSum=0
    for ((_i = 0; _i < 3; _i++)); do
        if (( _rowSum[_i] > _maxSum )); then _maxSum=${_rowSum[_i]}; fi
        if (( _colSum[_i] > _maxSum )); then _maxSum=${_colSum[_i]}; fi
    done
    _i=0; _j=0
    while (( _i < 3 && _j < 3 )); do
        local _diffR=$(( _maxSum - _rowSum[_i] ))
        local _diffC=$(( _maxSum - _colSum[_j] ))
        local _diff=$(( _diffR < _diffC ? _diffR : _diffC ))
        _m[_i*3+_j]=$(( _m[_i*3+_j] + _diff ))
        _rowSum[_i]=$(( _rowSum[_i] + _diff ))
        _colSum[_j]=$(( _colSum[_j] + _diff ))
        if (( _rowSum[_i] == _maxSum )); then ((_i++)); fi
        if (( _colSum[_j] == _maxSum )); then ((_j++)); fi
    done
    _out=("${_m[@]}")
}