C- print 99 multiplication table

Here's a complete list of the bottom triangle and nine nines ：

1*1=1   
1*2=2   2*2=4   
1*3=3   2*3=6   3*3=9   
1*4=4   2*4=8   3*4=12  4*4=16  
1*5=5   2*5=10  3*5=15  4*5=20  5*5=25  
1*6=6   2*6=12  3*6=18  4*6=24  5*6=30  6*6=36  
1*7=7   2*7=14  3*7=21  4*7=28  5*7=35  6*7=42  7*7=49  
1*8=8   2*8=16  3*8=24  4*8=32  5*8=40  6*8=48  7*8=56  8*8=64  
1*9=9   2*9=18  3*9=27  4*9=36  5*9=45  6*9=54  7*9=63  8*9=72  9*9=81  

For any given 1 Positive integer N, Output from 1*1 To N*N Part of the formula table .

Input format ：

Input gives a positive integer on a line N（1<=N<=9）.

Output format ：

Output the lower triangle N*N Part of the formula table , The number to the right of the equal sign is 4 position 、 Align left .

sample input ：

4

sample output ：

1*1=1   
1*2=2   2*2=4   
1*3=3   2*3=6   3*3=9   
1*4=4   2*4=8   3*4=12  4*4=16 

Code details ：

#include<stdio.h>
int main()
{
    int n;
    scanf("%d",&n);
    
    int i,j;
    i=1;
    while(i<=n){
        j=1;
        while(j<=i){
            printf("%d*%d=%d",i,j,i*j);
            if(i*j<10){
                printf("   ");
            }else{
                printf("  ");
            }
            j++;
        }
        printf("\n");
        i++;
    } 
}

First enter a variable n, For user input , Variable i,j Is the number of rows and columns of the multiplication table . According to the title, we can see that the format is x*y form , So it can be inferred that a two-layer loop . According to the space after each number , Can make a judgment , If it's a single digit , Print three spaces , If it is two digits, print two spaces .

The result is shown in the figure ：