Decimal to Hexadecimal number conversion: code: #include<stdio.h> int main() { int num,i,j,g[10]; scanf("%d",&num); char h[6]; h[0]='A'; h[1]='B'; h[2]='C'; h[3]='D'; h[4]='E'; h[5]='F'; for(i=0;num!=0;i++) { g[i]=num%16; num=num/16; } for(i=i-1;i>=0;i--) { if(g[i]>9) { j=g[i]-10; printf("%c",h[j]); } else ...