Create matdiagonalsum.cpp

oops408 · web-flow · commit b46cb201992f · 2023-05-08T08:54:02.000-07:00
diff --git a/c++/leetcode/matdiagonalsum.cpp b/c++/leetcode/matdiagonalsum.cpp
@@ -0,0 +1,11 @@
+class Solution {
+public:
+    int diagonalSum(vector<vector<int>>& mat) {
+        int sum=0,n=mat.size(),i=0,j=n-1;
+        while(i<n and j>=0){
+            sum+=(mat[i][i] + mat[i][j]);
+            i++; j--;
+        }
+        return (n%2) ? sum-mat[n/2][n/2] : sum;
+    }
+};
