tape_equilibrium() {
    local -n _a="$1"
    local _firstPart=0
    local _secondPart=0
    local _v
    for _v in "${_a[@]}"; do _secondPart=$(( _secondPart + _v )); done
    local _min=9223372036854775807
    local _i
    for ((_i = 0; _i < ${#_a[@]} - 1; _i++)); do
        _firstPart=$(( _firstPart + _i ))
        _secondPart=$(( _secondPart - _i ))
        local _diff=$(( _firstPart - _secondPart ))
        (( _diff < 0 )) && _diff=$(( -_diff ))
        (( _diff < _min )) && _min=$_diff
    done
    echo "$_min"
}

triangle() {
    local -n _a="$1"
    local -a _sorted=($(printf '%s\n' "${_a[@]}" | sort -n))
    local _c=${#_sorted[@]}
    if (( _c < 3 )); then
        echo 0
        return
    fi
    local _i
    for ((_i = 0; _i < _c - 2; _i++)); do
        if (( _sorted[_i] > 0 && _sorted[_i] > _sorted[_i+2] - _sorted[_i+1] )); then
            echo 1
            return
        fi
    done
    echo 0
}