Envío 4251

Código

import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.lang.Integer;
public class Main {
    static class Reader {
		final private int BUFFER_SIZE = 1 << 16;
		private DataInputStream din;
		private byte[] buffer;
		private int bufferPointer, bytesRead;

		public Reader() {
			din = new DataInputStream(System.in);
			buffer = new byte[BUFFER_SIZE];
			bufferPointer = bytesRead = 0;
		}

		public Reader(String file_name) throws IOException {
			din = new DataInputStream(new FileInputStream(file_name));
			buffer = new byte[BUFFER_SIZE];
			bufferPointer = bytesRead = 0;
		}

		public String readLine() throws IOException {
			byte[] buf = new byte[64]; // line length
			int cnt = 0, c;
			while ((c = read()) != -1) {
				if (c == '\n')
					break;
				buf[cnt++] = (byte) c;
			}
			return new String(buf, 0, cnt);
		}

		public int nextInt() throws IOException {
			int ret = 0;
			byte c = read();
			while (c <= ' ')
				c = read();
			boolean neg = (c == '-');
			if (neg)
				c = read();
			do {
				ret = ret * 10 + c - '0';
			} while ((c = read()) >= '0' && c <= '9');

			if (neg)
				return -ret;
			return ret;
		}

		public long nextLong() throws IOException {
			long ret = 0;
			byte c = read();
			while (c <= ' ')
				c = read();
			boolean neg = (c == '-');
			if (neg)
				c = read();
			do {
				ret = ret * 10 + c - '0';
			} while ((c = read()) >= '0' && c <= '9');
			if (neg)
				return -ret;
			return ret;
		}

		public double nextDouble() throws IOException {
			double ret = 0, div = 1;
			byte c = read();
			while (c <= ' ')
				c = read();
			boolean neg = (c == '-');
			if (neg)
				c = read();

			do {
				ret = ret * 10 + c - '0';
			} while ((c = read()) >= '0' && c <= '9');

			if (c == '.') {
				while ((c = read()) >= '0' && c <= '9') {
					ret += (c - '0') / (div *= 10);
				}
			}

			if (neg)
				return -ret;
			return ret;
		}

		private void fillBuffer() throws IOException {
			bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
			if (bytesRead == -1)
				buffer[0] = -1;
		}

		private byte read() throws IOException {
			if (bufferPointer == bytesRead)
				fillBuffer();
			return buffer[bufferPointer++];
		}

		public void close() throws IOException {
			if (din == null)
				return;
			din.close();
		}
	}
    public static void main(String[] args) throws Exception {
        Reader s = new Reader();
        int size = s.nextInt();
        
        int[][] arr = new int[size][size];
        int sum = 0;
        Integer mag = null;
        int diag1 = 0;
        int diag2 = 0;
       for (int i = 0; i < size; i++) {
        sum = 0;
        for (int j = 0; j < size; j++) {
            arr[i][j] =s.nextInt(); 
            sum += arr[i][j];
            if(i == j){diag1 += arr[i][j];}
            if(i+j+1 == size){diag2 += arr[i][j];}
            if(j+1 == size){
              if(mag == null){
               mag = sum;
              }
              if(mag != sum){
               System.out.println("No");return;
              }
            }
        }
       }
       if(diag1 != mag || diag2 != mag){
          System.out.println("No");return;
       }
    for (int j = 0; j < size; j++) {
        sum = 0;
        for (int i = 0; i < size; i++) {
           sum += arr[i][j];
           if(j+1 == size && mag != sum){ 
           System.out.println("No");return; }
        }
    }
       System.out.println("Yes");
      
    }
}