Perfect Number, Patterns , DecimalToBinary

Alphabet_Pattern.c

@@ -0,0 +1,27 @@
+/* 
+A
+B C
+D E F
+G H I J
+K L M N O
+*/
+
+#include <stdio.h>
+
+int main()
+{
+    int num,i=0,j,k;
+    printf("Enter the number : ");
+    scanf("%d",&num);
+    for(j=1;j<num+1;j++)
+    {
+        for(k=0;k<j;k++)
+        {
+            printf("%c ",(65 +i));
+            i++;
+        }
+        printf("\n");
+    }
+
+    return 0;
+}

Aplhabet_Pattern2.c

@@ -0,0 +1,28 @@
+/* 
+A
+B B
+C C C
+D D D D
+E E E E E
+*/
+
+#include <stdio.h>
+
+int main()
+{
+    int num,i=0,j,k;
+    printf("Enter the number : ");
+    scanf("%d",&num);
+    for(j=1;j<num+1;j++)
+    {
+        for(k=0;k<j;k++)
+        {
+            printf("%c ",(65 +i));
+
+        }
+        i++;
+        printf("\n");
+    }
+
+    return 0;
+}

DecimalToBinary.c

@@ -0,0 +1,19 @@
+#include <stdio.h>
+
+int main()
+{
+    int num, arr[100],i,j;
+    printf("Enter the number : ");
+    scanf("%d",&num);
+    for(i=0;num>0;i++)
+    {
+        arr[i] = num%2;
+        num = num/2;
+    }
+    for(j=i-1;j>=0;j--)
+    {
+        printf("%d",arr[j]);
+    }
+
+    return 0;
+}

NumberPattern.c

@@ -0,0 +1,26 @@
+/* 
+1
+2 3
+3 4 5
+6 7 8 9
+10 11 12 13 14 
+*/
+
+#include <stdio.h>
+
+int main()
+{
+    int num,i=1,j,k;
+    printf("Enter the number : ");
+    scanf("%d",&num);
+    for(j=1;j<num+1;j++)
+    {
+        for(k=0;k<j;k++)
+        {
+            printf("%d ",i++);
+        }
+        printf("\n");
+    }
+
+    return 0;
+}

Perfect Number.c

@@ -0,0 +1,19 @@
+#include <stdio.h>
+
+int main()
+{
+    int num,i,sum=0;
+    printf("Enter the number : ");
+    scanf("%d",&num);
+    for(i=1;i<=num/2;i++)
+    {
+        if(num % i == 0)
+            sum += i;
+    }
+    if(num == sum)
+        printf("It is a perfect number");
+    else
+        printf("It is not a perfect number");
+
+    return 0;
+}