C语言代码：
#include <stdio.h> int main() { int i, j; i=j=1; for (i=1;i<10;i++) { for (j=1;j<=i;j++) { printf("%dx%d=%2d ", i, j, i*j); } printf("\n"); } return 0; }
输出结果
1x1= 1 2x1= 2 2x2= 4 3x1= 3 3x2= 6 3x3= 9 4x1= 4 4x2= 8 4x3=12 4x4=16 5x1= 5 5x2=10 5x3=15 5x4=20 5x5=25 6x1= 6 6x2=12 6x3=18 6x4=24 6x5=30 6x6=36 7x1= 7 7x2=14 7x3=21 7x4=28 7x5=35 7x6=42 7x7=49 8x1= 8 8x2=16 8x3=24 8x4=32 8x5=40 8x6=48 8x7=56 8x8=64 9x1= 9 9x2=18 9x3=27 9x4=36 9x5=45 9x6=54 9x7=63 9x8=72 9x9=81
python代码：
for i in range(1,10): for j in range(1,10): if j <= i: print(f"{i}x{j}={‘%2d‘%(i*j)} ",end=‘‘) print()
输出结果
1x1= 1 2x1= 2 2x2= 4 3x1= 3 3x2= 6 3x3= 9 4x1= 4 4x2= 8 4x3=12 4x4=16 5x1= 5 5x2=10 5x3=15 5x4=20 5x5=25 6x1= 6 6x2=12 6x3=18 6x4=24 6x5=30 6x6=36 7x1= 7 7x2=14 7x3=21 7x4=28 7x5=35 7x6=42 7x7=49 8x1= 8 8x2=16 8x3=24 8x4=32 8x5=40 8x6=48 8x7=56 8x8=64 9x1= 9 9x2=18 9x3=27 9x4=36 9x5=45 9x6=54 9x7=63 9x8=72 9x9=81
原文：https://www.cnblogs.com/profesor/p/12815490.html