[Konstantinos]

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pawn Код:

new
    payment
;
if( weight > 9 && weight <= 50 ) payment = 100;
else if( weight > 50 && weight <= 100 ) payment = 150;
else if( weight > 100 && weight <= 150 ) payment = 200;
else if( weight > 150 && weight <= 200 ) payment = 250;
else payment = 0;

// -- OR --

new
    payment
;
switch( weight )
{
    case 10 .. 50: payment = 100;
    case 51 .. 100: payment = 150;
    case 101 .. 150: payment = 200;
    case 151 .. 200: payment = 250;
    default: payment = 0;
}