P135 杨辉三角形

常规写法，非递归。这里测试要从第二行开始输出。

#include <iostream>

using namespace std;

int Triangle[1000][1000];

void getAngle(int n){
    Triangle[1][1] = 1;
    Triangle[2][1] = 1;
    Triangle[2][2] = 1;
    for (int i = 3; i <= n; i++){
        for (int j = 1; j <= i; j++){
            Triangle[i][j] = Triangle[i - 1][j - 1] + Triangle[i - 1][j];
        }
    }
    for (int i = 2; i <= n; i++){
        for (int j = 1; j <= i; j++){
            if (j == i)
                cout << Triangle[i][j];
            else
                cout << Triangle[i][j] << " ";
        }
        cout << endl;
    }
}

int main(){
    int n;
    while(cin >> n){
        getAngle(n);
    }
    return 0;
}

递归写法

#include <iostream>

using namespace std;

int Triangle[1000][1000];

int func(int i, int j){
    if(j == 1 || i == j){
        return 1;
    }else{
        return func(i-1, j-1) + func(i-1, j);
    }
}

int main(){
    int n;
    while(cin >> n){
        for(int i = 2; i <= n; i++){
            for(int j = 1; j <= i; j++){
                if(j == 1){
                    cout << func(i, j);
                }else{
                    cout << " " << func(i, j);
                }
            }
            cout << endl;
        }
    }
    return 0;
}