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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#711590 | #8340. 3 Sum | professor_panda | WA | 362ms | 37568kb | C++17 | 3.4kb | 2024-11-05 12:21:55 | 2024-11-05 12:21:57 |
Judging History
answer
// https://qoj.ac/contest/1540/problem/8340
#include <bits/stdc++.h>
#define fastio ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
using namespace std;
/*
Three random primes between 10^8 and 10^9 are:
815583701
564956243
521310523
Generated with randome_prime.cpp
*/
typedef long long LL;
int N, K;
vector<int> mod_M[505];
vector<LL> mod_P[505];
int NUM_PRIMES = 3;
vector<LL> primes = {815583701, 564956243, 521310523};
set<LL> targets[3];
LL mod_prime(vector<int> n, LL p) {
LL res = 0;
for (int i = 0; i < K; i++) {
res = (res * 10 + n[i]) % p;
}
return res;
}
vector<int> add(const vector<int>& a, const vector<int>& b) {
vector<int> res(a.begin(), a.end());
bool carry = 0;
for (int w = K-1; w >= 0; w--) {
res[w] += b[w] + carry;
carry = res[w] > 9;
res[w] %= 10;
}
if (!carry) return res;
vector<int> one(K, 0);
one[K-1] = 1;
return add(res, one);
}
vector<int> simplify(const vector<int>& a) {
bool all_9 = true;
for (int i = 0; i < K; i++) {
if (a[i] != 9) {
all_9 = false;
break;
}
}
if (!all_9) return a;
return vector(K,0);
}
vector<int> inverse(const vector<int>& a) {
vector<int> res(K, 0);
bool all_zero = true;
for (int i = 0; i < K; i++) {
res[i] = 9 - a[i];
if (a[i]) all_zero = false;
}
if (all_zero) return vector<int>(K, 0);
return res;
}
vector<int> parse(string s) {
vector<int> res(K, 0);
int carry = 0;
bool done_str = false;
for (;;) {
for (int i = 0; i< K; i++) {
if (!done_str) {
int pos = s.size() - 1 - i;
while (pos >= 0) {
res[K-i-1] += s[pos] - '0';
pos -= K;
}
}
res[K-i-1] += carry;
carry = res[K-i-1] / 10;
res[K-i-1] %= 10;
if (done_str && !carry) break;
}
done_str = true;
if (!carry) break;
}
bool all_9 = true;
for (int i = 0; i < K; i++) {
if (res[i] != 9) {
all_9 = false;
break;
}
}
if (all_9) return vector<int>(K, 0);
return res;
}
int main() {
cin >> N >> K;
for (int i = 0; i < N; i++) {
string s;
cin >> s;
mod_M[i] = parse(s);
mod_P[i] = vector<LL>(NUM_PRIMES, 0);
for (int j=0; j < NUM_PRIMES; j++) {
mod_P[i][j]=mod_prime(mod_M[i], primes[j]);
}
}
vector<int> M = vector<int>(K, 9);
for (int i = 0; i < NUM_PRIMES; i++) {
targets[i] = set<LL>();
targets[i].insert(0);
LL a = mod_prime(M, primes[i]);
targets[i].insert(a);
targets[i].insert(2*a % primes[i]);
}
int cnt = 0;
for (int i = 0; i < N; i++) {
for (int j = i; j < N; j++) {
for (int k = j; k < N; k++) {
bool ok = true;
for (int l = 0; l < NUM_PRIMES; l++) {
if (targets[l].find(mod_P[i][l] + mod_P[j][l] + mod_P[k][l]) == targets[l].end()) {
ok = false;
break;
}
}
if (!ok) continue;
// TODO: verify?
if (ok) cnt++;
}
}
}
cout << cnt<< endl;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 0ms
memory: 3788kb
input:
4 1 0 1 10 17
output:
3
result:
ok 1 number(s): "3"
Test #2:
score: 0
Accepted
time: 80ms
memory: 5332kb
input:
500 859 7118711592236878297922359501613604144948355616986970837340677671376753603836852811886591300370143151943368529129749813118476151865844255212534355441611481420938483178075143062691345257288242460282715389758789648541099090735875617822348551942134616963557723055980260082230902505269975518146286...
output:
0
result:
ok 1 number(s): "0"
Test #3:
score: 0
Accepted
time: 362ms
memory: 37568kb
input:
500 17336 11871159223687829792235950161360414494835561698697083734067767137675360383685281188659130037014315194336852912974981311847615186584425521253435544161148142093848317807514306269134525728824246028271538975878964854109909073587561782234855194213461696355772305598026008223090250526997551814628...
output:
0
result:
ok 1 number(s): "0"
Test #4:
score: 0
Accepted
time: 198ms
memory: 3720kb
input:
500 1 751324443898124078584847834484321089092662321556147445230263526014359393841194947303407593948729802551881289193716611867931891257925091769456350249725997883453296895094445731130479434019358742162771547784250401546380268386074363779242500860317042151185119666027858022664683818314351285215150806...
output:
2327631
result:
ok 1 number(s): "2327631"
Test #5:
score: 0
Accepted
time: 214ms
memory: 3692kb
input:
500 2 408542968136435277974575411503179002415404345446801430469044749372949272333801248935236224652806667129749035002588943020176263162139056819871274824302889304493205266143688886696157147111754418731401856424401766968832165255416237731963027205324149660112574729610391396555581935236134531799950318...
output:
212002
result:
ok 1 number(s): "212002"
Test #6:
score: -100
Wrong Answer
time: 277ms
memory: 25932kb
input:
500 11500 75411775796562109942642493394321873284995260953010112281856775261847503626737348402159485133662757032091519863427156582689971229143089317472838196453888261138079171290535429921921548971897026706656838415620603757605079012541561774699628665865662183868374645956694140356716037674688084770628...
output:
10
result:
wrong answer 1st numbers differ - expected: '7675', found: '10'