【题目链接】
【算法】
按ai * bi升序排序,贪心即可
【代码】
#include<bits/stdc++.h>
using namespace std;
#define MAXN 1010
#define MAXL 10000struct info {
int l,r;
} a[MAXN];
int i,n;
struct INT {
int len;
int num[MAXL];
} sum,ans,val;template <typename T> inline void read(T &x) {
int f = ; x = ;
char c = getchar();
for (; !isdigit(c); c = getchar()) { if (c == '-') f = -f; }
for (; isdigit(c); c = getchar()) x = (x << ) + (x << ) + c - '';
x *= f;
}
template <typename T> inline void write(T x) {
if (x < ) { putchar('-'); x = -x; }
if (x > ) write(x/);
putchar(x%+'');
}
template <typename T> inline void writeln(T x) {
write(x);
puts("");
}
inline bool cmp(info a,info b) { return a.l * a.r < b.l * b.r; }
inline void multipy(INT &x,int y) {
int i;
for (i = ; i < x.len; i++) x.num[i] *= y;
for (i = ; i < x.len; i++) {
if (x.num[i] >= ) {
x.num[i+] += x.num[i] / ;
x.num[i] %= ;
}
}
while (x.num[x.len]) {
if (x.num[x.len] >= ) {
x.num[x.len+] += x.num[x.len] / ;
x.num[x.len] %= ;
}
x.len++;
}
}
inline INT divide(INT x,int y) {
int i,t=;
static INT ret;
ret.len = ;
for (i = x.len - ; i >= ; i--) {
t = t * + x.num[i];
ret.num[ret.len++] = t / y;
t %= y;
}
reverse(ret.num,ret.num+ret.len);
while (ret.num[ret.len-] == && ret.len > ) ret.len--;
return ret;
}
inline bool comp(INT x,INT y) {
int i;
if (x.len < y.len) return true;
if (y.len < x.len) return false;
for (i = x.len - ; i >= ; i--) {
if (x.num[i] < y.num[i]) return true;
if (y.num[i] > x.num[i]) return false;
}
return false;
}
inline void print(INT x) {
int i;
for (i = x.len - ; i >= ; i--) write(x.num[i]);
puts("");
}int main() { read(n);
read(a[].l); read(a[].r);
for (i = ; i <= n; i++) {
read(a[i].l);
read(a[i].r);
}
sort(a+,a+n+,cmp);
sum.len = ; sum.num[] = ; for (i = ; i <= n; i++) {
multipy(sum,a[i-].l);
val = divide(sum,a[i].r);
if (comp(ans,val)) ans = val;
}
print(ans); return ;}