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#include<bits/stdc++.h>
using namespace std;
int main()
{
int row_num;
cin>>row_num;
int val = 1,sum=1;
for(int r = 1; r <= row_num; r++)
{
val = val * (row_num - r)/r;
sum=sum+val;
}
cout<<sum<<endl;
return 1;
}
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1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1
1 6 15 20 15 6 1
1 7 21 35 35 21 7 1
1 8 28 56 70 56 28 8 1
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class Solution {
public:
vector<vector<int>> generate(int numRows) {
vector<vector<int>> r(numRows);
for (int i = 0; i < numRows; i++) {
r[i].resize(i + 1);
r[i][0] = r[i][i] = 1;
for (int j = 1; j < i; j++)
r[i][j] = r[i - 1][j - 1] + r[i - 1][j];
}
return r;
}
};