Arjun Suresh (talk | contribs) |
Arjun Suresh (talk | contribs) |
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#include <string.h> | #include <string.h> | ||
#include <ctype.h> | #include <ctype.h> | ||
− | + | ||
void print(char *a, int l); | void print(char *a, int l); | ||
int read(char *a); | int read(char *a); | ||
− | + | ||
int main(void) { | int main(void) { | ||
char a[1000], b[1000], c[1000], carry; //a and b hold the input numbers and c hold the output number. Each array entry is a digit | char a[1000], b[1000], c[1000], carry; //a and b hold the input numbers and c hold the output number. Each array entry is a digit | ||
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printf("Enter the first number "); | printf("Enter the first number "); | ||
al = read(a); | al = read(a); | ||
− | |||
printf("Enter the second number "); | printf("Enter the second number "); | ||
bl = read(b); | bl = read(b); | ||
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return 0; | return 0; | ||
} | } | ||
− | + | ||
int read(char *a) | int read(char *a) | ||
{ | { | ||
char c; | char c; | ||
int i = 0; | int i = 0; | ||
− | + | do | |
{ | { | ||
c = getchar(); | c = getchar(); | ||
− | + | } | |
− | + | while(isspace(c)); | |
+ | while(isdigit(c)) | ||
+ | { | ||
a[i++] = c - 48; //getchar returns the ASCII. So, for 1 it returns 49. Subtracting 48, we get the actual int value entered via keyboard | a[i++] = c - 48; //getchar returns the ASCII. So, for 1 it returns 49. Subtracting 48, we get the actual int value entered via keyboard | ||
+ | c = getchar(); | ||
} | } | ||
return i; | return i; | ||
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printf("\n"); | printf("\n"); | ||
} | } | ||
− | |||
</syntaxhighlight> | </syntaxhighlight> | ||
<syntaxhighlight lang="c" name="largesum">
void print(char *a, int l); int read(char *a);
int main(void) { char a[1000], b[1000], c[1000], carry; //a and b hold the input numbers and c hold the output number. Each array entry is a digit int al, bl; //for storing the number of digits of the two input numbers printf("Enter the first number "); al = read(a); printf("Enter the second number "); bl = read(b); int l = al > bl? al:bl;//l stores the no.of digit of output which might also become l+1 because of carry from MSB int i = l; carry = 0; while(al > 0 && bl > 0) { char val = a[--al] + b[--bl] + carry; c[i--] = val % 10; carry = val / 10; } while(al > 0)//If a has more digits than b { char val = a[--al] + carry;
c[i--] = val % 10; carry = val / 10;
} while(bl > 0)//If b has more digits than a { char val = b[--bl] + carry;
c[i--] = val % 10; carry = val / 10;
} c[0] = carry;//Assigning the final carry printf("sum = "); print(c, l+1); return 0; }
int read(char *a) { char c; int i = 0; do { c = getchar(); } while(isspace(c)); while(isdigit(c)) { a[i++] = c - 48; //getchar returns the ASCII. So, for 1 it returns 49. Subtracting 48, we get the actual int value entered via keyboard c = getchar(); } return i; } void print(char *a, int l) { int i; if(a[0] != 0) printf("%d", a[0]); for(i = 1; i < l; i++) { printf("%d", a[i]); } printf("\n"); } </syntaxhighlight>
<syntaxhighlight lang="c" name="largesum">
void print(char *a, int l); int read(char *a);
int main(void) { char a[1000], b[1000], c[1000], carry; //a and b hold the input numbers and c hold the output number. Each array entry is a digit int al, bl; //for storing the number of digits of the two input numbers printf("Enter the first number "); al = read(a); fflush(stdin); //Removes any previous character entered via keyboard printf("Enter the second number "); bl = read(b); int l = al > bl? al:bl;//l stores the no.of digit of output which might also become l+1 because of carry from MSB int i = l; carry = 0; while(al > 0 && bl > 0) { char val = a[--al] + b[--bl] + carry; c[i--] = val % 10; carry = val / 10; } while(al > 0)//If a has more digits than b { char val = a[--al] + carry;
c[i--] = val % 10; carry = val / 10;
} while(bl > 0)//If b has more digits than a { char val = b[--bl] + carry;
c[i--] = val % 10; carry = val / 10;
} c[0] = carry;//Assigning the final carry printf("sum = "); print(c, l+1); return 0; }
int read(char *a) { char c; int i = 0; while(1) { c = getchar(); if(!isdigit(c)) break; a[i++] = c - 48; //getchar returns the ASCII. So, for 1 it returns 49. Subtracting 48, we get the actual int value entered via keyboard } return i; } void print(char *a, int l) { int i; if(a[0] != 0) printf("%d", a[0]); for(i = 1; i < l; i++) { printf("%d", a[i]); } printf("\n"); }
</syntaxhighlight>