青蛙兔子这题C++用int数据溢出
如题,换成long long就通过了,看题目说明是10^9,压根没往这块想,提交了很多次总是不通过,最后试了下long long,瞬间AC。话说咱们出题也严谨点,而且不通过的case能不能给个case的数据,一直在这憋着也太难受了。附代码:
#include <iostream>
#include <math.h>
using namespace std;
typedef long long ll;
void gcd(ll a, ll b, ll& g, ll &x, ll &y) {
if (b == 0) {
g = a;
x = 1;
y = 0;
return;
}
gcd(b, a % b, g, y, x);
y -= x * (a / b);
}
int main() {
int cnt;
cin >> cnt;
while(cnt-- > 0) {
ll a, b, n, l, r;
cin >> a >> b >> n >> l >> r;
ll g, x, y;
gcd(a, b, g, x, y);
if (n % g != 0) {
cout << "NO" << endl;
continue;
}
x *= n / g;
y *= n / g;
ll b_ = b / g;
ll a_ = a / g;
ll minK = ceil((l - x) * 1.0 / b_);
ll maxK = floor(min((r - x) * 1.0 / b_, y * 1.0 / a_));
if (maxK < minK) {
cout << "NO" << endl;
continue;
}
cout << "YES" << endl;
}
return 0;
}
主要思路是套用二元一次方程整数解模板,利用通解公式施加条件,进而确定k的范围。附模板链接:https://www.luogu.com.cn/problem/solution/P5656

