[js] 贪心算法

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            //找零问题
            function makeChange(origAmt, coins) {
                var remainAmt = 0;
                if (origAmt % .25 < origAmt) {
                    coins[3] = parseInt(origAmt / .25);
                    remainAmt = origAmt % .25;
                    origAmt = remainAmt;
                }
                if (origAmt % .1 < origAmt) {
                    coins[2] = parseInt(origAmt / .1);
                    remainAmt = origAmt % .1;
                    origAmt = remainAmt;
                }
                if (origAmt % .05 < origAmt) {
                    coins[1] = parseInt(origAmt / .05);
                    remainAmt = origAmt % .05;
                    origAmt = remainAmt;
                }
                coins[0] = parseInt(origAmt / .01);
            }

            function showChange(coins) {
                if (coins[3] > 0) {
                    console.log("Number of quarters - " + coins[3] + " - " + coins[3] * .25);
                }
                if (coins[2] > 0) {
                    console.log("Number of dimes - " + coins[2] + " - " + coins[2] * .10);
                }
                if (coins[1] > 0) {
                    console.log("Number of nickels - " + coins[1] + " - " + coins[1] * .05);
                }
                if (coins[0] > 0) {
                    console.log("Number of pennies - " + coins[0] + " - " + coins[0] * .01);
                }
            }
            var origAmt = .63;
            var coins = [];
            makeChange(origAmt, coins);
            showChange(coins);
            //背包问题
            function ksack(values, weights, capacity) {
                var load = 0;
                var i = 0;
                var w = 0;
                while (load < capacity && i < 4) {
                    if (weights[i] <= (capacity - load)) {
                        w += values[i];
                        load += weights[i];
                    } else {
                        var r = (capacity - load) / weights[i];
                        w += r * values[i];
                        load += weights[i];
                    }
                    ++i;
                }
                return w;
            }
            var items = ["A", "B", "C", "D"];
            var values = [50, 140, 60, 60];
            var weights = [5, 20, 10, 12];
            var capacity = 30;
            console.log(ksack(values, weights, capacity)); // 220