37 lines
1008 B
C++
37 lines
1008 B
C++
class Solution {
|
|
public:
|
|
int findTargetSumWays(vector<int>& nums, int S) {
|
|
if (S < -1000 || S>1000) return 0;
|
|
|
|
int sz = nums.size();
|
|
int msz = sizeof(int) * 2048;
|
|
int _bin[2048] = { 0 };
|
|
int _xbin[2048] = { 0 };
|
|
int* p = _bin;
|
|
int* q = _xbin;
|
|
memset(p, 0, msz);
|
|
p[1000] = 1;
|
|
|
|
for (int i = 0; i < sz; i++)
|
|
{
|
|
memset(q, 0, msz);
|
|
for (int j = 0; j < 2048; j++)
|
|
{
|
|
if (p[j])
|
|
{
|
|
//printf("p[%d]=%d\n", p[j]);
|
|
// now=j-1000;
|
|
int L = j - nums[i]; // now-nums[i]+1000
|
|
int R = j + nums[i];
|
|
q[L] += p[j];
|
|
q[R] += p[j];
|
|
//printf("q[%d]=%d\n", L, q[L]);
|
|
//printf("q[%d]=%d\n", R, q[R]);
|
|
}
|
|
}
|
|
std::swap(p, q);
|
|
}
|
|
return p[S + 1000];
|
|
}
|
|
};
|