Why the second code executes within 500ms whereas the first one gives TLE(2000ms) ?
1497E1 - Square-Free Division (easy version)
const int N = 1e7 + 5;
vector<int> maping(N);
int i,j;
Code 1
Code 2
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Why the second code executes within 500ms whereas the first one gives TLE(2000ms) ?
1497E1 - Square-Free Division (easy version)
const int N = 1e7 + 5;
vector<int> maping(N);
int i,j;
for (i = 1; i < N; i++) {
maping[i] = i;
}
for (i = 2; i < N; i++) {
for (j = 2; j * j <= i; j++) {
while (maping[i] % (j * j) == 0) maping[i] = maping[i] / (j * j);
}
}
for (i = 1 ; i < N ; i++) maping[i] = i;
for (i = 2; i < N; i++) {
for (j = i * i; j <= N; j += i * i) {
while (maping[j] % (i * i) == 0) {
maping[j] = maping[j] / (i * i);
}
}
}
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