#include <algorithm>
#include <ctime>
#include <cstdlib>
 
struct S {
    S(int i = 0, int j = 0) {
        arr[0] = i;
        arr[1] = j;
    }
    int arr[2];
    int & operator[](int i){
        return arr[i];
    }
    const int & operator[](int i) const {
        return arr[i];
    }
};
 
int main(){
    srand(time(0U));
    S arr[10];
    for(int i = 0; i < 10; i++){
        arr[i] = S(rand(), rand());
    }
    std::sort(arr, arr + 10, [] (const S &a, const S &b){
        if(a[0] != b[0]) return a[0] < a[1];
        return a[1] < b[1];
    });
}

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