'commit'

TangDou/LianXiTi50/29.cpp

@@ -0,0 +1,20 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+const int N = 10;
+int a[N][N];
+
+int main() {
+    int n = 3;
+    for (int i = 1; i <= n; i++)
+        for (int j = 1; j <= n; j++)
+            cin >> a[i][j];
+
+    int s = 0;
+    for (int i = 1; i <= n; i++)
+        for (int j = 1; j <= n; j++)
+            if (i == j) s += a[i][j];
+
+    cout << s << endl;
+    return 0;
+}