#include <bits/stdc++.h>
using namespace std;
int main(){
ios_base::sync_with_stdio(0);
cout.tie(0); cin.tie(0);
int n; cin>>n;
vector<int> squares(n+1, 0);
for(int i=1; i<=n; i++) squares[i] = i*i;
map<int, int> diff;
for(int i=n; i>=1; i--){
for(int j=i-1; j>=1; j--){
diff[squares[i] - squares[j]]++;
}
}
int answer = 0;
for(int i=1; i<=n; i++){
for(int j=i; j<=n; j++){
int sum = squares[i] + squares[j];
answer += diff[sum];
}
}
cout<<answer;
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 | #include <bits/stdc++.h> using namespace std; int main(){ ios_base::sync_with_stdio(0); cout.tie(0); cin.tie(0); int n; cin>>n; vector<int> squares(n+1, 0); for(int i=1; i<=n; i++) squares[i] = i*i; map<int, int> diff; for(int i=n; i>=1; i--){ for(int j=i-1; j>=1; j--){ diff[squares[i] - squares[j]]++; } } int answer = 0; for(int i=1; i<=n; i++){ for(int j=i; j<=n; j++){ int sum = squares[i] + squares[j]; answer += diff[sum]; } } cout<<answer; return 0; } |
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