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;(function (root, factory, undef) {
    if (typeof exports === "object") {
        // CommonJS
        module.exports = exports = factory(require("./core"), require("./cipher-core"));
    }
    else if (typeof define === "function" && define.amd) {
        // AMD
        define(["./core", "./cipher-core"], factory);
    }
    else {
        // Global (browser)
        factory(root.CryptoJS);
    }
}(this, function (CryptoJS) {
    /**
     * Output Feedback block mode.
     */
    CryptoJS.mode.OFB = (function () {
        var OFB = CryptoJS.lib.BlockCipherMode.extend();
        var Encryptor = OFB.Encryptor = OFB.extend({
            processBlock: function (words, offset) {
                // Shortcuts
                var cipher = this._cipher
                var blockSize = cipher.blockSize;
                var iv = this._iv;
                var keystream = this._keystream;
                // Generate keystream
                if (iv) {
                    keystream = this._keystream = iv.slice(0);
                    // Remove IV for subsequent blocks
                    this._iv = undefined;
                }
                cipher.encryptBlock(keystream, 0);
                // Encrypt
                for (var i = 0; i < blockSize; i++) {
                    words[offset + i] ^= keystream[i];
                }
            }
        });
        OFB.Decryptor = Encryptor;
        return OFB;
    }());
    return CryptoJS.mode.OFB;
}));
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