多项选择题
执行代码片段,用于输出字符数组ch中每个字符出现的次数publicstaticvoidmain(String[]args){char[]ch={’a’,’c’,’a’,’b’,’c’,’b’};HashMapmap=newHashMap();for(inti=0;i
A.if(map.contains(ch[i])){map.put(ch[i],map.get(ch[i])+1);}else{map.put(ch[i],1);}
B.if(map.contains(ch[i])){map.put(ch[i],(Integer)map.get(ch[i])+1);}else{map.put(ch[i],1);}
C.if(map.containsKey(ch[i])){map.put(ch[i],(int)map.get(ch[i])+1);}else{map.put(ch[i],1);}
D.if(map.containsKey(ch[i])){map.put(ch[i],(Integer)map.get(ch[i])+1);}else{map.put(ch[i],1);}
A.if(map.contains(ch[i])){map.put(ch[i],map.get(ch[i])+1);}else{map.put(ch[i],1);}
B.if(map.contains(ch[i])){map.put(ch[i],(Integer)map.get(ch[i])+1);}else{map.put(ch[i],1);}
C.if(map.containsKey(ch[i])){map.put(ch[i],(int)map.get(ch[i])+1);}else{map.put(ch[i],1);}
D.if(map.containsKey(ch[i])){map.put(ch[i],(Integer)map.get(ch[i])+1);}else{map.put(ch[i],1);}
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D.编译运行都正确,输出结果为2
