lanqiao 1457 杨辉三角形(朴素解法)

12lanqiao/test8-1.cpp

@@ -0,0 +1,28 @@
+// lanqiao 1457 杨辉三角形(朴素解法)
+#include<bits/stdc++.h>
+using namespace std;
+#define int long long 
+const int N = 1e3 + 10;
+int a[N][N];
+signed main(){
+    int n; cin >>n;
+    if(n == 1){
+        cout << 1 << endl;
+        return 0;
+    } 
+    a[1][1] = a[2][1] = a[2][2] = 1;
+    for(int i = 3; i <= N-1; i++){
+        for(int j = 1; j <= i; j++){
+            if(j == 1 || j == i) a[i][j] = 1;
+            else a[i][j] = a[i-1][j] + a[i-1][j-1];
+            if(a[i][j] == n){ // 1 + 2 + ... + i-1
+                cout << i*(i-1)/2 + j << endl;
+                return 0;
+            }
+        }
+    }
+    return 0;
+}
+/* test samples -> 13
+6
+*/