①

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>int main()
{for (int i = 1; i <= 9; i++){for (int j = 1; j <= i; j++){printf("%d*%d=%d\t", j, i, i * j);}printf("\n");}return 0;
}

②

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>int main()
{for (int i = 1; i <= 9; i++){for (int j = i; j <= 9; j++){printf("%d*%d=%d\t", j, i, i * j);}printf("\n");}return 0;
}