# C Program to find union and intersection of two strings

In this program, You will learn how to find union and intersection of two strings in c.

``````1st is: a b c d e

2nd is: d e f

The union is: a b c d e f

The intersection is: d e``````

## Example: How to find union and intersection of two strings in c.

``````#include<stdio.h>
#include<string.h>

void findUnion(char str1[], char str2[]) {

int f, p = 0;
int i, j;

char str3[100];
int len1 = strlen(str1);
int len2 = strlen(str2);

while (str1[p] != '\0') {
str3[p] = str1[p];
p++;
}

for (i = 0; i < len2; i++) {
f = 0;
for (j = 0; j < len1; j++) {
if (str2[i] == str1[j]) {
f = 1;
}
}
if (f == 0) {
str3[p] = str2[i];
p++;
}
}
str3[p] = '\0';
printf("Union of two strings:%s", str3);
}

void findIntersection(char str1[], char str2[]) {

int i, j, k = 0;
char str3[100];

int len1 = strlen(str1);
int len2 = strlen(str2);

for (i = 0; i < len1; i++) {
for (j = 0; j < len2; j++) {
if (str1[i] == str2[j]) {
str3[k] = str1[i];
k++;
}
}
}
str3[k] = '\0';
printf("\nIntersection of two strings:%s", str3);
}

int main() {

char str1[100];
char str2[100];
char str3[100];

printf("Enter First String :");
scanf("%[^\n]%*c", str1);

printf("Enter Second String :");
scanf("%[^\n]%*c", str2);

findUnion(str1, str2);
findIntersection(str1, str2);

return 0;
}``````

#### Output:

``````Enter First String :abcd
Enter Second String :bcd
Union of two strings:abcd
Intersection of two strings:bcd``````