21.09.13模拟 分割金币
给定n个数,要求分成两堆,使得两堆的和的差值最小的差值和最小差值方案数
一遍背包即可,求出f_i=凑出和为i的一堆金币的方案数,那么凑出tot-f_i的方案数也会是f_i
贪心的从平均分配到不平均分配找即可
#include
#include
#define rep(i,j,k) for(register int i(j);i<=k;++i)
#define drp(i,j,k) for(register int i(j);i>=k;--i)
#define bug cout<<"~~~~~~~~~~~~~"<<'\n';
#define bugout(x) cout<
inline T max(T &a, T &b) {
return a > b ? a : b;
}
template
inline T min(T &a, T &b) {
return a < b ? a : b;
}
inline char gt() {
static char buf[1 << 21], *p1 = buf, *p2 = buf;
return p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 21, stdin), p1 == p2) ? EOF : *p1++;
}
template
inline void read(T &x) {
register char ch = gt();
x = 0;
int w(0);
while(!(ch >= '0' && ch <= '9'))w |= ch == '-', ch = gt();
while(ch >= '0' && ch <= '9')x = x * 10 + (ch & 15), ch = gt();
w ? x = ~(x - 1) : x;
}
template
inline void out(T x, char cc) {
if(x < 0) x = -x, putchar('-');
char ch[20];
int num(0);
while(x || !num) ch[++num] = x % 10 + '0', x /= 10;
while(num) putchar(ch[num--]);
putchar(cc);
}
const int N = 1007;
const int M = 257 * 1007;
int n, tot, a[N];
int f[M];
int main() {
freopen("divgold.in", "r", stdin);
freopen("divgold.out", "w", stdout);
read(n);
rep(i, 1, n) {
read(a[i]);
tot += a[i];
}
f[0] = 1;
rep(i, 1, n)
drp(j, tot, a[i]) {
f[j] = (f[j] + f[j - a[i]]) % 1000000;
}//±3°ü
int num = 0, t = 0;
drp(j, tot/2,0) {
if(f[j]) {
t = tot - 2 * j;
num = f[j];
break;
}
}
out(t, '\n');
out(num, '\n');
return 0;
}