416. Partition Equal Subset Sum
class Solution {
public:
bool canPartition(vector<int>& nums) {
int sum = 0;
for(auto num : nums) sum += num;
if(sum % 2) return false;
sum /= 2;
vector<bool> dp(sum+1, false);
dp[0] = true;
for(int ii = 1; ii < nums.size(); ii++) {
for(int jj = sum; jj > 0; jj--) {
if(nums[ii] <= jj) dp[jj] = dp[jj] || dp[jj - nums[ii]];
}
}
return dp[sum];
}
};
class Solution {
public:
bool canPartition(vector<int>& nums) {
int sum = 0;
for(auto num : nums) sum += num;
if(sum % 2) return false;
sum /= 2;
vector<vector<bool> > dp(nums.size(), vector<bool>(sum+1, false));
for(int ii = 0; ii < nums.size(); ii++) {
dp[ii][0] = true;
if(nums[ii] <= sum) dp[ii][nums[ii]] = true;
}
for(int ii = 1; ii < nums.size(); ii++) {
for(int jj = 1; jj <= sum; jj++) {
if(nums[ii] <= jj) dp[ii][jj] = dp[ii-1][jj-nums[ii]];
dp[ii][jj] = dp[ii][jj] || dp[ii-1][jj];
}
}
return dp[nums.size()-1][sum];
}
};