In this program, You will learn how to find the sum of diagonal elements of a matrix in c.

```
1 2 3
4 5 6
7 8 9
1 + 5 + 9 = 15
```

## Example: How to find the sum of diagonal elements of a matrix in c.

```
#include<stdio.h>
int main() {
int arr[10][10];
int n,i,j,sum=0;
printf("Enter size of matrix:");
scanf("%d",&n);
printf("Enter matrix elements:");
for (i = 0; i < n; i++) {
for(j = 0; j < n;j++){
scanf("%d", &arr[i][j]);
}
}
printf("All matrix elements:\n");
for (i = 0; i < n; i++) {
for(j = 0; j < n; j++){
printf("%d ", arr[i][j]);
}
printf("\n");
}
printf("List is: ");
for(i = 0; i < n; i++){
printf("%d ",arr[i][i]);
sum = sum + arr[i][i];
}
printf("\nSum of Diagonal is:%d", sum);
return 0;
}
```

#### Output:

```
Enter matrix elements:1 2 3 4 5 6 7 8 9
All matrix elements:
1 2 3
4 5 6
7 8 9
List is: 1 5 9
Sum of Diagonal is:15
```