C :

#include<stdio.h>

int main()
{
	int n,m,i,j,a;
	int top,bottom,left,right;
	int arr[100][100];
	scanf("%d %d",&n,&m);
	i=0;
	j=0;
	a=1;
	top=0;
	bottom=0;
	left=0;
	right=0;
	while(top+bottom<n&&left+right<m)
	{
	    if(top+bottom<n)
		{
		    for(i=top,j=left;j<m-right;j++)
			{
			    arr[i][j]=a;
				a++;
			}
			top++;
		}
		if(left+right<m)
		{
		    for(j=m-right-1,i=top;i<n-bottom;i++)
			{
			    arr[i][j]=a;
				a++;
			}
			right++;
		}
	    if(top+bottom<n)
		{
		    for(i=n-bottom-1,j=m-right-1;j>=left;j--)
			{
			    arr[i][j]=a;
				a++;
			}
			bottom++;
		}
		if(left+right<m)
		{
		    for(j=left,i=n-bottom-1;i>=top;i--)
			{
			    arr[i][j]=a;
				a++;
			}
			left++;
		}
	}
	
	for(i=0;i<n;i++)
	{
	    for(j=0;j<m;j++)
		{
		    printf("%d ",arr[i][j]);
		}
		printf("\n");
	}


    return 0;
}

C++ :

#include <iostream>

using namespace std;
const int N = 105;

int a[N][N];
int n, m;

int main() {
    cin >> n >> m;

    int left = 0, right = m - 1, top = 0, bottom = n - 1;
    int k = 1;
    while (left <= right && top <= bottom) {
        for (int i = left ; i <= right; i ++) {
            a[top][i] = k ++;
        }
        for (int i = top + 1; i <= bottom; i ++) {
            a[i][right] = k ++;
        }
        for (int i = right - 1; i >= left && top < bottom; i --) {
            a[bottom][i] = k ++;
        }
        for (int i = bottom - 1; i > top && left < right; i --) {
            a[i][left] = k ++;
        }
        left ++, right --, top ++, bottom --;
    }
    for (int i = 0; i < n; i ++) {
        for (int j = 0; j < m; j ++) {
            cout << a[i][j] << " ";
        }
        cout << endl;
    }
    return 0;
}