单词替换，现需要将其中的某个单词替换成另一个单词，并输出替换之后的字符串。

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#include <bits/stdc++.h>
using namespace std;
string a[110],b,d;
int main()
{
    int n =0 ,c=0;
    while(cin>>a[c])
    {
        c++;
        char x=getchar();
        if(x=='\n')
        break;
        
    }
    cin>>b>>d;
    for(int i = 0 ;i < c;i++)
    {
        if(a[i]==b)
        cout<<d<<" ";
        else cout<<a[i]<<" ";
    }
}