#include <iostream>
#include <algorithm>
using namespace std;
bool BothAreSpaces(char lhs, char rhs) { return (lhs == rhs) && (lhs == ' '); }
int main() {
string str;
getline(cin, str);
str.erase(unique(str.begin(), str.end(), BothAreSpaces), str.end());
cout << str;
return 0;
}
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