(function(){
var k=this||self,l=function(a){var b=typeof a;return b=="object"&&a!=null||b=="function"},m=function(a,b){function c(){}c.prototype=b.prototype;a.l=b.prototype;a.prototype=new c;a.prototype.constructor=a;a.s=function(d,e,f){for(var g=Array(arguments.length-2),h=2;h=0);return b},v=function(){var a=t,b=u;a.classList?a.classList.remove(b):r(a,b)&&q(a,Array.prototype.filter.call(a.classList?a.classList:p(a).match(/\S+/g)||[],function(c){return c!=
b}).join(" "))};var w=function(a,b){this.type=a;this.target=b};w.prototype.g=function(){};var x=function(){if(!k.addEventListener||!Object.defineProperty)return!1;var a=!1,b=Object.defineProperty({},"passive",{get:function(){a=!0}});try{var c=function(){};k.addEventListener("test",c,b);k.removeEventListener("test",c,b)}catch(d){}return a}();var y=function(a){w.call(this,a?a.type:"");this.relatedTarget=this.target=null;this.button=this.screenY=this.screenX=this.clientY=this.clientX=0;this.key="";this.keyCode=0;this.metaKey=this.shiftKey=this.altKey=this.ctrlKey=!1;this.state=null;this.pointerId=0;this.pointerType="";this.i=null;if(a){var b=this.type=a.type,c=a.changedTouches&&a.changedTouches.length?a.changedTouches[0]:null;this.target=a.target||a.srcElement;var d=a.relatedTarget;d||(b=="mouseover"?d=a.fromElement:b=="mouseout"&&(d=a.toElement));this.relatedTarget=d;c?(this.clientX=c.clientX!==void 0?c.clientX:c.pageX,this.clientY=c.clientY!==void 0?c.clientY:c.pageY,this.screenX=c.screenX||0,this.screenY=c.screenY||0):(this.clientX=a.clientX!==void 0?a.clientX:a.pageX,this.clientY=a.clientY!==void 0?a.clientY:a.pageY,this.screenX=a.screenX||0,this.screenY=a.screenY||0);this.button=a.button;this.keyCode=a.keyCode||0;this.key=a.key||"";this.ctrlKey=a.ctrlKey;this.altKey=a.altKey;this.shiftKey=a.shiftKey;this.metaKey=a.metaKey;this.pointerId=
a.pointerId||0;this.pointerType=a.pointerType;this.state=a.state;this.i=a;a.defaultPrevented&&y.l.g.call(this)}};m(y,w);y.prototype.g=function(){y.l.g.call(this);var a=this.i;a.preventDefault?a.preventDefault():a.returnValue=!1};var z="closure_listenable_"+(Math.random()*1E6|0);var A=0;var B=function(a,b,c,d,e){this.listener=a;this.proxy=null;this.src=b;this.type=c;this.capture=!!d;this.i=e;this.key=++A;this.g=this.j=!1},C=function(a){a.g=!0;a.listener=null;a.proxy=null;a.src=null;a.i=null};var D=function(a){this.src=a;this.g={};this.i=0};D.prototype.add=function(a,b,c,d,e){var f=a.toString();a=this.g[f];a||(a=this.g[f]=[],this.i++);var g;a:{for(g=0;g-1?(b=a[g],c||(b.j=!1)):(b=new B(b,this.src,f,!!d,e),b.j=c,a.push(b));return b};var E="closure_lm_"+(Math.random()*1E6|0),F={},G=0,I=function(a,b,c,d,e){if(d&&d.once)return H(a,b,c,d,e);if(Array.isArray(b)){for(var f=0;f=0)&&Array.prototype.splice.call(e,f,1);g&&(C(a),c.g[d].length==0&&(delete c.g[d],c.i--))}c.i==0&&(c.src=null,b[E]=null)}else C(a)}}},N=function(a){return a in F?F[a]:F[a]="on"+a},O=function(a,b){if(a.g)a=!0;else{b=new y(b,this);var c=a.listener,d=a.i||a.src;a.j&&P(a);a=c.call(d,b)}return a},L=function(a){a=a[E];return a instanceof D?a:null},Q="__closure_events_fn_"+(Math.random()*1E9>>>0),J=function(a){if(typeof a==="function")return a;a[Q]||(a[Q]=function(b){return a.handleEvent(b)});return a[Q]};var R=[9],u,t=document.documentElement,S;function T(){P(S);S=H(t,"mousedown",function(){v();U()},{capture:!0})}function U(){P(S);S=I(t,"keydown",function(a){if(R.indexOf(a.keyCode)!==-1){a=t;var b=u;if(a.classList)a.classList.add(b);else if(!r(a,b)){var c=p(a);q(a,c+(c.length>0?" "+b:b))}T()}})};u="zAoYTe";U();}).call(this);(function(){var c=500;(function(){window.screen&&window.screen.width<=c&&window.screen.height<=c&&document.getElementById("hdr").classList.add("sml");}).call(this);})(); AllBooksShoppingImages Maps Videos News Search tools Any time
- Any time
- Past hour
- Past 24 hours
- Past week
- Past month
- Past year
All results
(function(){var a=document.getElementById("st-toggle"),b=document.getElementById("st-card");a&&b&&a.addEventListener("click",function(c){b.style.display=b.style.display?"":"none";c.preventDefault()},!1);}).call(this);Your search - cache:DNKlsZh5QwIJ:www.edu.cn - did not match any documents.
Suggestions:
Make sure all words are spelled correctly.
Try different keywords.
Try more general keywords.
(function(){var hl='en';(function(){var g=function(a){var b=0;return function(){return b>>0)+"_",d=0,e=function(h){if(this instanceof e)throw new TypeError("Symbol is not a constructor");return new b(c+(h||"")+"_"+d++,h)};return e});n("Symbol.iterator",function(a){if(a)return a;a=Symbol("Symbol.iterator");for(var b="Array Int8Array Uint8Array Uint8ClampedArray Int16Array Uint16Array Int32Array Uint32Array Float32Array Float64Array".split(" "),c=0;c
0?"0l"+P.length:"")}
function X(){S=null;if(T){var a={client:"heirloom-srp",hl:hl,json:"t",callback:"hS",q:T};typeof ds!=="undefined"&&ds&&(a.ds=ds);var b=document;var c="SCRIPT";b.contentType==="application/xhtml+xml"&&(c=c.toLowerCase());c=b.createElement(c);b=F(ca);var d=C(b).toString();var e=d.split(/[?#]/),h=/[?]/.test(d)?"?"+e[1]:"";b=e[0];d=/[#]/.test(d)?"#"+(h?e[2]:e[1]):"";a=G(b,h,d,a);c.src=C(a);var f;a=c.ownerDocument&&c.ownerDocument.defaultView||window;a=a===void 0?document:a;var w;a=(w=(f="document"in a?a.document:a).querySelector)==null?void 0:w.call(f,"script[nonce]");(f=a==null?"":a.nonce||a.getAttribute("nonce")||"")&&c.setAttribute("nonce",f);document.body.appendChild(c);T=null;S=setTimeout(X,500)}}function Y(){for(;M.firstChild;)M.removeChild(M.firstChild);P=[];Q=-1;V(!1)}function Z(){var a=M.querySelector(".scs");a&&(a.className="");Q>=0?(a=M.childNodes[Q],a.className="scs",O=a.textContent):O=R;K.value=O}K.addEventListener("focus",function(){H&&(H.style.display="none")},!1);K.addEventListener("blur",function(){Y();H&&(H.style.display="")},!1);K.addEventListener("keyup",function(a){O=K.value;U=!1;a.which===13?W():a.which===27?(Y(),H&&(H.style.display=""),O=R,K.value=O):a.which===40?(Q++,Q>=P.length&&(Q=-1),Z()):a.which===38?(Q--,Q<-1&&(Q=P.length-1),Z()):(a=O)?(N&&(N.style.display=""),T=a,S||X(),R=a):(N&&(N.style.display="none"),V(!1),Y(),R="",U=!0)},!1);L.addEventListener("click",W,!1);N.addEventListener("click",function(){K.value="";N.style.display="none";V(!1)},!1);J.addEventListener("click",function(){K.focus()},!1);window.hS=function(a){if(!U){Y();a[1].length===0&&V(!1);for(var b=0;b/g,"");d.addEventListener("click",function(e){return function(){Q=e;W();Z();Y();I.submit()}}(b),!1);d.addEventListener("mouseover",function(e){return function(){Q!==e&&(Q=e,Z())}}(b),!1);M.appendChild(d);V(!0);P.push(c)}}};}).call(this);})();(function(){function b(a){for(a=a.target||a.srcElement;a&&a.nodeName!=="A";)a=a.parentElement;a&&(a.href||"").match(/\/search.*[?&]tbm=isch/)&&(a.href+="&biw="+document.documentElement.clientWidth,a.href+="&bih="+document.documentElement.clientHeight)}document.addEventListener("click",b,!1);document.addEventListener("touchStart",b,!1);}).call(this);(function(){var e='cScxZ-i3CeyxkPIP_9yc8Ao';var sn='web';var timl=false;(function(){function D(a){if(!a||E(a))return 0;if(!a.getBoundingClientRect)return 1;var c=function(b){return b.getBoundingClientRect()};return F(a,c)?0:K(a,c)}function F(a,c){var b;a:{for(b=a;b&&b!==null;b=b.parentElement)if(b.style.overflow==="hidden"||b.tagName==="G-EXPANDABLE-CONTENT"&&getComputedStyle(b).getPropertyValue("overflow")==="hidden")break a;b=null}if(!b)return!1;a=c(a);c=c(b);return a.bottom=c.bottom||a.right=c.right}
function E(a){return a.style.display==="none"?!0:document.defaultView&&document.defaultView.getComputedStyle?(a=document.defaultView.getComputedStyle(a),!!a&&(a.visibility==="hidden"||a.height==="0px"&&a.width==="0px")):!1}
function K(a,c){var b=c(a);a=b.left+window.pageXOffset;c=b.top+window.pageYOffset;var f=b.width;b=b.height;var g=0;if(b<=0&&f<=0)return g;var u=window.innerHeight||document.documentElement.clientHeight;c+b<0?g=2:c>=u&&(g=4);if(a+f<0||a>=(window.innerWidth||document.documentElement.clientWidth))g|=8;g||(g=1,c+b>u&&(g|=4));return g};
var L=(this||self).JSON.parse;var M=e,N=sn,O=typeof de==="undefined"?!0:de!==!1,P=location,Q=[];function R(a,c,b){a="/gen_204?atyp=csi&s="+N+"&t="+a+("&lite=1&ei="+M+"&conn="+(window.navigator&&window.navigator.connection?window.navigator.connection.type:-1)+c);c="&rt=";for(var f in b)a+=""+c+f+"."+b[f],c=",";return a}function S(a){a={prt:a};window.wsrt&&(a.wsrt=window.wsrt);return a}function T(a){window.ping?window.ping(a):(new Image).src=a}
(function(){for(var a=(new Date).getTime()-window.start,c=S(a),b=0,f=0,g=0,u=document.getElementsByTagName("img"),v=O?"&biw="+window.innerWidth+"&bih="+window.innerHeight:"",G=function(){v+="&ima="+g;c.aft=b;T(R("aft",v,c))},z=0,U=function(d,l,p){var m=d.src;d.onload=function(){p&&m&&m===d.src||(f=(new Date).getTime()-window.start,l&&++z===g&&(b=f,G()),d.onload=null)}},V=0,h=void 0;h=u[V++];){var w=D(h),t=!!(w&1);t&&++g;var q=h.hasAttribute("data-ilite"),x=h.hasAttribute("data-deferred"),H=h.hasAttribute("data-src")||
h.hasAttribute("data-lzysrc"),A=!x&&!q&&H;Q.push([w,x||q,A,h.id,q&&H]);q=(w=h.complete&&!x&&!(t&&A))&&Number(h.getAttribute("data-iml"))||0;w&&q?(t&&++z,q&&(h=q-window.start,t&&(b=Math.max(b,h)),f=Math.max(f,h))):U(h,t,x||A)}b||(b=a);f||(f=b);z===g&&G();google.rglh&&google.rglh();window.addEventListener("load",function(){window.setTimeout(function(){c.ol=(new Date).getTime()-window.start;timl&&(c.iml=f);var d=window.performance&&window.performance.timing;if(d){c.rqst=d.responseEnd-d.requestStart;c.rspt=d.responseEnd-d.responseStart;a:{if(d=(d=P.search.match(RegExp("[?&]sei=([^]*)")))&&d[1]){b:{try{var l=window.sessionStorage.getItem("sg_pns;;"+d);if(l){var p=l.indexOf("_");var m=p<0?null:L(l.substr(p+1))}else m=null;var n=m;break b}catch(W){}n=null}if(n){n=window.performance.timing.navigationStart-Number(n);try{window.sessionStorage.removeItem("sg_pns;;"+d)}catch(W){}d=n;break a}}d=void 0}d&&d>0&&(c.sgl=d)}for(var I=p=m=l=n=d=0,X=0,k;k=Q[X++];){var r=k[0],B=k[1],J=k[2],y=k[3];k=k[4]||google.ldi&&
y&&google.ldi[y];y=r==0;var Y=r&8,C=r&1;r=!C&&r&4;C&&(B&&!k||++l,J&&++I);B&&(C&&k&&++d,r&&!k&&++n);y||Y?J||++p:B||++m}v+="&ime="+l+"&imel="+I+("&imex="+m+"&imeh="+p)+("&imea="+d+"&imeb="+n);T(R("all",v,c))},0)},!1)})();}).call(this);})();(function(){window.google=window.google||{};window.google.ishk=[];function a(){return window.scrollY+window.document.documentElement.clientHeight>=Math.max(document.body.scrollHeight,document.body.offsetHeight)}function b(){a()&&window.google.ishk.length===0&&(window.google.bs=!0,window.removeEventListener("scroll",b))}a()?window.google.bs=!0:(window.google.bs=!1,window.addEventListener("scroll",b));}).call(this);(function(){var e='cScxZ-i3CeyxkPIP_9yc8Ao';(function(){var a=e;if((window.performance&&window.performance.navigation&&window.performance.navigation.type)===2){var b="",c=[],d=window.google!==void 0&&window.google.kOPI!==void 0&&window.google.kOPI!==0?window.google.kOPI:null;d!=null&&c.push(["opi",d.toString()]);for(var f=0;f0)b+="&";b+=c[f][0]+"="+c[f][1]}window.ping("/gen_204?ct=backbutton&ei="+a+b)};}).call(this);})();(function(){var e='cScxZ-i3CeyxkPIP_9yc8Ao';(function(){var d=["blur","pagehide"],g=["focus","pageshow"],h=[0,0,0,0],k=e||"",m=new XMLHttpRequest,n=h,p=0,q="1",r=1,t=1,u=0,v=function(a){var b=Date.now();q+=":"+(b-u)+","+a.join(",");u=b;r++},w=0,x=0,G=function(){for(var a=0,b=void 0;b=d[a];a++)window.addEventListener(b,y);a=0;for(b=void 0;b=g[a];a++)window.addEventListener(b,z);window.addEventListener("scroll",function(){w||(w=setTimeout(z,500))});window.addEventListener("visibilitychange",D);window.addEventListener("click",function(c){setTimeout(function(){x||
(x=setTimeout(E,500));var f=c.target;f.tagName==="a"||f.tagName==="A"?F("C"):f.parentElement==null||f.parentElement.tagName!=="a"&&f.parentElement.tagName!=="A"||F("C")},0)})},E=function(){var a=document.body.offsetHeight;p!==a&&(v(["T"]),H(),x=0,p=a)},D=function(){document.visibilityState!=="hidden"?z():y()},F=function(a){v(["e",a]);a="/gen_204?ct=slh&v=t2&me="+q+"&s="+t+"&ei="+k;window.navigator&&navigator.sendBeacon?navigator.sendBeacon(a):(m.open("GET",a),m.send());q=""+r;t++;u=0},y=function(){n=
h;v(["V"].concat(n));clearTimeout(w);w=0;F("H")},z=function(){var a=[Math.round(window.pageXOffset),Math.round(window.pageYOffset),Math.round(window.innerWidth),Math.round(window.innerHeight)];if(a[2]===n[2]&&a[3]===n[3]){if(a[0]!==n[0]||a[1]!==n[1]){var b=["S",a[1]-n[1]];a[0]-n[0]>0&&b.push(a[0]-n[0]);v(b)}}else v(["V"].concat(a));n=a;w=0},H=function(){for(var a=document.querySelectorAll("[data-hveid]"),b=0;b0:!1}function w(){return u("Safari")&&!(x()||(v()?0:u("Coast"))||(v()?0:u("Opera"))||(v()?0:u("Edge"))||(v()?t("Microsoft Edge"):u("Edg/"))||(v()?t("Opera"):u("OPR"))||u("Firefox")||u("FxiOS")||u("Silk")||u("Android"))}function x(){return v()?t("Chromium"):(u("Chrome")||u("CriOS"))&&!(v()?0:u("Edge"))||u("Silk")}function y(){return u("Android")&&!(x()||u("Firefox")||u("FxiOS")||(v()?0:u("Opera"))||u("Silk"))};var z=v()?!1:u("Trident")||u("MSIE");y();x();w();var A=!z&&!w(),D=function(a){if(/-[a-z]/.test("ved"))return null;if(A&&a.dataset){if(y()&&!("ved"in a.dataset))return null;a=a.dataset.ved;return a===void 0?null:a}return a.getAttribute("data-"+"ved".replace(/([A-Z])/g,"-$1").toLowerCase())};var E=[],F=null;function G(a){a=a.target;var c=performance.now(),f=[],H=f.concat,d=E;if(!(d instanceof Array)){var m=typeof Symbol!="undefined"&&Symbol.iterator&&d[Symbol.iterator];if(m)d=m.call(d);else if(typeof d.length=="number")d={next:b(d)};else throw Error("b`"+String(d));for(var B=[];!(m=d.next()).done;)B.push(m.value);d=B}E=H.call(f,d,[c]);if(a&&a instanceof HTMLElement)if(a===F){if(c=E.length>=4)c=(E[E.length-1]-E[E.length-4])/1E3<5;if(c){c=google.getEI(a);a.hasAttribute("data-ved")?f=a?D(a)||"":"":f=(f=
a.closest("[data-ved]"))?D(f)||"":"";f=f||"";if(a.hasAttribute("jsname"))a=a.getAttribute("jsname");else{var C;a=(C=a.closest("[jsname]"))==null?void 0:C.getAttribute("jsname")}google.log("rcm","&ei="+c+"&tgtved="+f+"&jsname="+(a||""))}}else F=a,E=[c]}window.document.addEventListener("DOMContentLoaded",function(){document.body.addEventListener("click",G)});}).call(this);var w=function(a){var b=0;return function(){return b0?a.substring(0,t):"",u=document.createElement("div");u.innerHTML=b;var l=u.children[0];if(l&&(d.tag=l.tagName,d["class"]=String(l.className||null),d.name=String(l.getAttribute("jsname")),k)){a=[];var v=document.querySelectorAll('[id^="'+k+'_"]');for(b=0;b