C language printing diamond

Ideas ： To put it simply , First, we can divide the diamond into the upper half and the lower half , use 3 individual for Cycle through the top half , Reuse 3 individual for Cycle through the bottom half , as for for Why is the judgment condition in the loop written like this , Just remember , Don't ask why , If you ask , It is logical .....

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main() {
	int i, j, k;
	for (i = 0; i <= 3; i++) { // Control the number of rows in the upper half 
		for (j = 0; j <= 2 - i; j++) {  
			printf(" ");   // Print spaces by using the correspondence of the number of lines 
		}
		for (k = 0; k <= 2*i; k++) { 
			printf("*");   // Print the asterisk with the correspondence of the number of lines 
		}
		printf("\n");
	}
	
	for (i = 0; i <= 2; i++) {  // Control the number of rows in the lower half 
		for (j = 0; j <= i; j++) {
			printf(" ");    Print spaces by using the correspondence of the number of lines 
		}
		for (k = 0; k <= 4 - 2 * i; k++) {
			printf("*");  // Print the asterisk with the correspondence of the number of lines 
		}
		printf("\n");
	}
	
	return 0;
}